Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2017	Feb. 20, 2018	Jun. 30, 2017
Document and Entity Information [Abstract]
Entity Registrant Name	ACADIA REALTY TRUST
Entity Central Index Key	0000899629
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Common Stock, Shares Outstanding		83,735,086
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 2,347.5

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
ASSETS
Operating real estate, net	$ 2,952,918	$ 2,551,448
Real estate under development	173,702	543,486
Net investments in real estate	3,126,620	3,094,934
Notes receivable, net	153,829	276,163
Investments in and advances to unconsolidated affiliates	302,070	272,028
Other assets, net	214,959	192,786
Cash and cash equivalents	74,823	71,805
Rents receivable, net	51,738	43,842
Restricted cash	10,846	22,904
Assets of properties held for sale	25,362	21,498
Total assets	3,960,247	3,995,960
LIABILITIES
Mortgage and other notes payable, net	909,174	1,055,728
Unsecured notes payable, net	473,735	432,990
Unsecured line of credit	41,500	0
Accounts payable and other liabilities	210,052	208,672
Capital lease obligation	70,611	70,129
Dividends and distributions payable	24,244	36,625
Distributions in excess of income from, and investments in, unconsolidated affiliates	15,292	13,691
Total liabilities	1,744,608	1,817,835
Commitments and contingencies
Acadia Shareholders' Equity
Common shares, $0.001 par value, authorized 200,000,000 and 100,000,000 shares, issued and outstanding 83,708,140 and 83,597,741 shares, respectively	84	84
Additional paid-in capital	1,596,514	1,594,926
Accumulated other comprehensive loss	2,614	(798)
Distributions in excess of accumulated earnings	(32,013)	(5,635)
Total Acadia shareholders’ equity	1,567,199	1,588,577
Noncontrolling interests	648,440	589,548
Total equity	2,215,639	2,178,125
Total liabilities and equity	$ 3,960,247	$ 3,995,960

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Common shares, par value (in dollars per share)	$ 0.001	$ 0.001
Common shares, authorized (in shares)	200,000,000	100,000,000
Common shares, issued (in shares)	83,708,140	83,597,741
Common shares, outstanding (in shares)	83,708,140	83,597,741

CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	12 Months Ended
CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues
Rental income	$ 198,941	$ 152,814	$ 158,632
Expense reimbursements	44,907	32,282	36,306
Other	6,414	4,843	4,125
Total revenues	250,262	189,939	199,063
Operating expenses
Depreciation and amortization	104,934	70,011	60,751
General and administrative	33,756	40,648	30,368
Real estate taxes	35,946	25,630	25,384
Property operating	41,668	24,244	28,423
Other operating	2,184	7,517	4,675
Impairment charges	14,455	0	5,000
Total operating expenses	232,943	168,050	154,601
Operating income	17,319	21,889	44,462
Equity in earnings and gains of unconsolidated affiliates inclusive of gains on disposition of properties of $15,336, $35,950 and $24,043, respectively	23,371	39,449	37,330
Interest income	29,143	25,829	16,603
Interest expense	(58,978)	(34,645)	(37,297)
Gain on change in control and other	5,571	0	1,596
Income from continuing operations before income taxes	16,426	52,522	62,694
Income tax (provision) benefit	(1,004)	105	(1,787)
Income from continuing operations before gain on disposition of properties	15,422	52,627	60,907
Gain on disposition of properties, net of tax	48,886	81,965	89,063
Net income	64,308	134,592	149,970
Net income attributable to noncontrolling interests	(2,838)	(61,816)	(84,262)
Net income attributable to Acadia	$ 61,470	$ 72,776	$ 65,708
Earnings Per Share, Basic and Diluted [Abstract]
Basic and diluted earnings per share (in dollars per share)	$ 0.73	$ 0.94	$ 0.94

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 64,308	$ 134,592	$ 149,970
Other comprehensive income (loss):
Unrealized income (loss) on valuation of swap agreements	634	(646)	(5,061)
Reclassification of realized interest on swap agreements	3,317	4,576	5,524
Other comprehensive income	3,951	3,930	463
Comprehensive income	68,259	138,522	150,433
Comprehensive income attributable to noncontrolling interests	(3,377)	(62,081)	(85,183)
Comprehensive income attributable to Acadia	$ 64,882	$ 76,441	$ 65,250

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Shares	Additional Paid-in Capital	Accumulated Other Comprehensive (Loss) Income	(Distributions in Excess of Accumulated Earnings) Retained Earnings	Total Common Shareholders’ Equity	Noncontrolling Interests
Beginning Balance at Dec. 31, 2014	$ 1,435,957	$ 68	$ 1,027,861	$ (4,005)	$ 31,617	$ 1,055,541	$ 380,416
Balance (in Shares) at Dec. 31, 2014		68,109,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership	0		2,451			2,451	(2,451)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership (in Shares)		101,000
Issuance of Common Shares, net of issuance costs	64,417	$ 2	64,415			64,417
Issuance of Common Shares, net of issuance costs (in Shares)		1,973,000
Dividends declared ($1.05, $1.16 and $1.22 per Common Share/OP Unit for Year Ended December 31, 2017, 2016 and 2015 respectively)	(90,666)				(84,683)	(84,683)	(5,983)
Acquisition of noncontrolling interests	(7,970)		(4,409)			(4,409)	(3,561)
Employee and trustee stock compensation, net	8,644		1,921			1,921	6,723
Employee and trustee stock compensation, net (in Shares)		75,000
Noncontrolling interest distributions	(74,950)						(74,950)
Noncontrolling interest contributions	35,489						35,489
Comprehensive income	150,433			(458)	65,708	65,250	85,183
Ending Balance at Dec. 31, 2015	1,521,354	$ 70	1,092,239	(4,463)	12,642	1,100,488	420,866
Balance (in Shares) at Dec. 31, 2015		70,258,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership	0	$ 1	7,891			7,892	(7,892)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership (in Shares)		351,000
Issuance of Common Shares, net of issuance costs	450,130	$ 13	450,117			450,130
Issuance of Common Shares, net of issuance costs (in Shares)		12,961,000
Issuance of OP Units to acquire real estate	31,429						31,429
Dividends declared ($1.05, $1.16 and $1.22 per Common Share/OP Unit for Year Ended December 31, 2017, 2016 and 2015 respectively)	(97,806)				(91,053)	(91,053)	(6,753)
Acquisition of noncontrolling interests	(18,379)		7,546			7,546	(25,925)
Employee and trustee stock compensation, net	13,694		926			926	12,768
Employee and trustee stock compensation, net (in Shares)		28,000
Change in control of previously unconsolidated investment	(75,713)						(75,713)
Windfall tax benefit	555		555			555
Noncontrolling interest distributions	(80,769)						(80,769)
Noncontrolling interest contributions	295,108						295,108
Reallocation of noncontrolling interests	0		35,652			35,652	(35,652)
Comprehensive income	138,522			3,665	72,776	76,441	62,081
Ending Balance at Dec. 31, 2016	$ 2,178,125	$ 84	1,594,926	(798)	(5,635)	1,588,577	589,548
Balance (in Shares) at Dec. 31, 2016	83,597,741	83,598,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership	$ 0		1,541			1,541	(1,541)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership (in Shares)		87,000
Dividends declared ($1.05, $1.16 and $1.22 per Common Share/OP Unit for Year Ended December 31, 2017, 2016 and 2015 respectively)	(94,301)				(87,848)	(87,848)	(6,453)
Employee and trustee stock compensation, net	11,155		698			698	10,457
Employee and trustee stock compensation, net (in Shares)		23,000
Noncontrolling interest distributions	(32,805)						(32,805)
Noncontrolling interest contributions	85,206						85,206
Reallocation of noncontrolling interests	0		(651)			(651)	651
Comprehensive income	68,259			3,412	61,470	64,882	3,377
Ending Balance at Dec. 31, 2017	$ 2,215,639	$ 84	$ 1,596,514	$ 2,614	$ (32,013)	$ 1,567,199	$ 648,440
Balance (in Shares) at Dec. 31, 2017	83,708,140	83,708,000

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 64,308	$ 134,592	$ 149,970
Adjustments to reconcile net income to net cash provided by operating activities:
Gain on disposition of properties	(48,886)	(81,965)	(89,063)
Gain on change in control	(5,571)	0	0
Depreciation and amortization	104,934	70,011	60,751
Distributions of operating income from unconsolidated affiliates	9,249	7,256	12,291
Equity in earnings and gains of unconsolidated affiliates	(23,371)	(39,449)	(37,330)
Stock compensation expense	11,155	13,695	7,438
Amortization of financing costs	5,985	3,204	3,537
Impairment charges	14,455	0	5,000
Other, net	(10,610)	(8,095)	(6,483)
Changes in assets and liabilities:
Other liabilities	(4,285)	26,532	5,354
Prepaid expenses and other assets	(6,498)	(11,677)	12,690
Rents receivable, net	(11,274)	(4,847)	(5,673)
Restricted cash	11,474	1,912	(6,168)
Accounts payable and accrued expenses	8,768	591	1,284
Net cash provided by operating activities	119,833	111,760	113,598
CASH FLOWS FROM INVESTING ACTIVITIES
Acquisition of real estate	(200,429)	(495,644)	(338,700)
Development and property improvement costs	(108,142)	(149,434)	(164,315)
Issuance of or advances on notes receivable	(10,600)	(157,352)	(48,500)
Proceeds from the disposition of properties	260,711	150,378	168,895
Investments in and advances to unconsolidated affiliates	(6,535)	(72,098)	(24,168)
Return of capital from unconsolidated affiliates	23,946	54,444	11,892
Proceeds from notes receivable	32,000	42,819	15,984
Deposits for properties under contract	(2,000)	1,424	(5,776)
Proceeds from disposition of properties of unconsolidated affiliates	26,045	24,586	38,392
Payment of deferred leasing costs	(5,202)	(7,515)	(8,207)
Change in control of previously unconsolidated (consolidated) affiliate	288	(2,578)	0
Net cash provided by (used in) investing activities	10,082	(610,970)	(354,503)
CASH FLOWS FROM FINANCING ACTIVITIES
Principal payments on mortgage and other notes	(306,119)	(394,864)	(148,423)
Principal payments on unsecured debt	(277,134)	(541,790)	(234,815)
Proceeds received on mortgage and other notes	156,344	222,071	90,234
Proceeds from unsecured debt	359,625	666,716	417,425
Proceeds from issuance of Common Shares, net of issuance costs of $0, $9,238 and $1,150, respectively	0	450,130	63,234
Capital contributions from noncontrolling interests	85,206	295,108	35,489
Distributions to noncontrolling interests	(39,942)	(105,994)	(84,610)
Dividends paid to Common Shareholders	(99,527)	(91,334)	(86,353)
Deferred financing and other costs	(6,211)	(11,678)	(4,376)
Loan proceeds held as restricted cash	861	9,874	48,676
Purchase of convertible notes payable	0	0	(380)
Net cash (used in) provided by financing activities	(126,897)	498,239	96,101
Increase (decrease) in cash and cash equivalents	3,018	(971)	(144,804)
Cash and cash equivalents, beginning of the year	71,805	72,776	217,580
Cash and cash equivalents, end of the year	74,823	71,805	72,776
Supplemental disclosure of cash flow information
Cash paid during the period for interest, net of capitalized interest of $13,509, $21,109 and $16,447, respectively	49,942	42,279	47,960
Cash paid for income taxes, net of (refunds)	875	2,036	2,038
Supplemental disclosure of non-cash investing activities
Acquisition of real estate through assumption of debt	0	120,672	91,885
Acquisition of real estate through issuance of OP Units	0	29,336	0
Acquisition of capital lease obligation	0	76,461	0
Mortgage debt financed at time of acquisition	0	63,900	0
Assumption of accounts payable and accrued expenses through acquisition of real estate	2,173	3,587	0
Assumption of prepaid expenses and other assets through acquisition of real estate		2,226	0
Disposition of air rights through issuance of notes receivable	0		(29,539)
Acquisition of real estate through assumption of restricted cash	0		(28,912)
Acquisition of real estate through conversion of note receivable	9,000	0	13,386
Acquisition of undivided interest in a property through conversion of notes receivable	60,695	0	0
Change in control of previously unconsolidated (consolidated) investment
(Increase) decrease in real estate, net	(39,322)	90,559	0
Gain on change in control	5,571	0	0
Decrease in notes receivable	32,010	0	0
Decrease (increase) in investments in and advances to unconsolidated affiliates	4,159	(21,421)	0
Decrease in noncontrolling interest	0	(75,713)	0
Change in other assets and liabilities	(2,130)	3,997	0
Increase (decrease) in cash upon change of control	$ 288	$ (2,578)	$ 0

Organization, Basis of Presentation and Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2017

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization, Basis of Presentation and Summary of Significant Accounting Policies

Organization

Acadia Realty Trust and subsidiaries (collectively, the “Company”) is a fully-integrated equity real estate investment trust (“REIT”) focused on the ownership, acquisition, development, and management of retail properties located primarily in high-barrier-to-entry, supply-constrained, densely-populated metropolitan areas in the United States.

All of the Company’s assets are held by, and all of its operations are conducted through, Acadia Realty Limited Partnership (the “Operating Partnership”) and entities in which the Operating Partnership owns an interest. As of December 31, 2017 and December 31, 2016, the Company controlled approximately 95% of the Operating Partnership as the sole general partner and is entitled to share, in proportion to its percentage interest, in the cash distributions and profits and losses of the Operating Partnership. The limited partners primarily represent entities or individuals that contributed their interests in certain properties or entities to the Operating Partnership in exchange for common or preferred units of limited partnership interest (“Common OP Units” or “Preferred OP Units”) and employees who have been awarded restricted Common OP Units (“LTIP Units”) as long-term incentive compensation (Note 13). Limited partners holding Common OP and LTIP Units are generally entitled to exchange their units on a one-for-one basis for common shares of beneficial interest of the Company (“Common Shares”). This structure is referred to as an umbrella partnership REIT or “UPREIT.”

As of December 31, 2017, the Company has ownership interests in 118 properties within its core portfolio, which consist of those properties either 100% owned, or partially owned through joint venture interests, by the Operating Partnership, or subsidiaries thereof, not including those properties owned through its funds (“Core Portfolio”). The Company also has ownership interests in 58 properties within its opportunity funds, Acadia Strategic Opportunity Fund II, LLC (“Fund II”), Acadia Strategic Opportunity Fund III LLC (“Fund III”), Acadia Strategic Opportunity Fund IV LLC (“Fund IV”), and Acadia Strategic Opportunity Fund V LLC (“Fund V”). Acadia Strategic Opportunity Fund I, LP (“Fund I,” together with Funds II, III, IV, and V, the “Funds”) was liquidated in 2015. The 176 Core Portfolio and Fund properties primarily consist of street and urban retail, and suburban shopping centers. In addition, the Company, together with the investors in the Funds, invest in operating companies through Acadia Mervyn Investors I, LLC (“Mervyns I”), Acadia Mervyn Investors II, LLC (“Mervyns II”) and Fund II, all on a non-recourse basis. The Company consolidates the Funds as it has (i) the power to direct the activities that most significantly impact the Funds’ economic performance, (ii) is obligated to absorb the Funds’ losses and (iii) has the right to receive benefits from the Funds that could potentially be significant.

The Operating Partnership is the sole general partner or managing member of the Funds and Mervyns I and II and earns fees or priority distributions for asset management, property management, construction, development, leasing, and legal services. Cash flows from the Funds and Mervyns I and II are distributed pro-rata to their respective partners and members (including the Operating Partnership) until each receives a certain cumulative return (“Preferred Return”) and the return of all capital contributions. Thereafter, remaining cash flow is distributed 20% to the Operating Partnership (“Promote”) and 80% to the partners or members (including the Operating Partnership). All transactions between the Funds and the Operating Partnership have been eliminated in consolidation.

The following table summarizes the general terms and Operating Partnership’s equity interests in the Funds and Mervyns II (dollars in millions):



Entity	Formation Date	Operating Partnership Share of Capital	Capital Called as of December 31, 2017		Unfunded Commitment		Equity Interest Held By Operating Partnership ^(a)	Preferred Return	Total Distributions as of December 31, 2017 ^(b)
Fund II and Mervyns II	6/2004	28.33%	$	347.1	$	—	28.33%	8%	$	131.6
Fund III	5/2007	24.54%	411.5		38.5		24.54%	6%	551.9
Fund IV	5/2012	23.12%	412.7		117.3		23.12%	6%	131.5
Fund V	8/2016	20.10%	45.8		474.2		20.10%	6%	—

__________


(a)	Amount represents the current economic ownership at December 31, 2017, which could differ from the stated legal ownership based upon the cumulative preferred returns of the respective fund.


(b)	Represents the total for the Funds, including the Operating Partnership and noncontrolling interests’ shares.

Basis of Presentation

Segments

At December 31, 2017, the Company had three reportable operating segments: Core Portfolio, Funds and Structured Financing. The Company’s chief operating decision maker may review operational and financial data on a property basis and does not differentiate properties on a geographical basis for purposes of allocating resources or capital. Each property is considered a separate operating segment; however, each property on a stand-alone basis represents less than 10% of revenues, profit or loss, and assets of the combined reported operating segment and meets the majority of the aggregations criteria under the applicable standard.

Principles of Consolidation

The consolidated financial statements include the consolidated accounts of the Company and its investments in partnerships and limited liability companies in which the Company has control in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 810 “Consolidation” (“ASC Topic 810”). The ownership interests of other investors in these entities are recorded as noncontrolling interests. All significant intercompany balances and transactions have been eliminated in consolidation. Investments in entities for which the Company has the ability to exercise significant influence over, but does not have financial or operating control, are accounted for using the equity method of accounting. Accordingly, the Company’s share of the earnings (or losses) of these entities are included in consolidated net income.

Cost Method Investments

The Company has certain investments to which it applies the cost method of accounting. The Company recognizes as income distributions from net accumulated earnings of the investee since the date of acquisition. The net accumulated earnings of an investee subsequent to the date of investment are recognized by the Company only to the extent distributed by the investee. Distributions received in excess of earnings subsequent to the date of investment are considered a return of investment and are recorded as reductions of cost of the investment. For the periods presented, there have been no events or changes in circumstances that may have a significant adverse effect on the fair value of the Company's cost-method investments.

Out-of-Period Adjustments

During the year ended December 31, 2016, the Company identified and recorded out-of-period adjustments related to accounting for certain leases whose tenants have early termination and renewal options and for interest expense related to a loan that is in default. The Company's management concluded that these non-cash adjustments are not material to the consolidated financial statements for any of the periods presented. The net impact of the adjustments on the consolidated statement of income for the year ended December 31, 2016 is reflected as a decrease to rental income of $2.1 million, an increase to depreciation and amortization expense of $1.7 million, an increase in interest expense of $0.7 million and an increase to equity in earnings of unconsolidated affiliates of $0.2 million, resulting in a net decrease to net income of $4.2 million, of which $1.6 million was attributable to noncontrolling interests.

During the second quarter of 2016, management determined that certain transactions involving the issuance of Common Shares of the Company and Common OP Units, Preferred OP Units, and LTIP Units of the Operating Partnership, should have resulted in an adjustment to the Operating Partnership’s non-controlling interest (“OPU NCI”) and the Company’s Additional Paid-in-Capital (“APIC”) to reflect the difference between the fair value of the consideration received or paid and the book value of the Common Shares, Common OP Units, Preferred OP Units, and LTIP Units involving these changes in ownership (the “Rebalancing”). During the year ended December 31, 2016, the Company increased its APIC with an offsetting reduction to the OPU NCI of approximately $35.7 million, of which approximately $31.8 million of this Rebalancing related to prior years. Management concluded that the Rebalancing adjustments were not meaningful to the Company’s financial position for any of the prior years, and the quarterly periods in 2016, and as such, this cumulative change was recorded in the consolidated balance sheet and statement of shareholder’s equity in the second quarter of 2016 as an out-of-period adjustment. The misclassification had no impact on the previously reported consolidated assets, liabilities or total equity or on the consolidated statements of income, comprehensive income, or cash flows.

Use of Estimates

GAAP requires the Company’s management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. The most significant assumptions and estimates relate to the valuation of real estate, depreciable lives, revenue recognition and the collectability of notes receivable and rents receivable. Application of these estimates and assumptions requires the exercise of judgment as to future uncertainties and, as a result, actual results could differ from these estimates.

Summary of Significant Accounting Policies

Real Estate

Land, buildings, and personal property are carried at cost less accumulated depreciation. Improvements and significant renovations that extend the useful life of the properties are capitalized, while replacements, maintenance, and repairs that do not improve or extend the lives of the respective assets are expensed as incurred. Real estate under development includes costs for significant property expansion and development.

Depreciation is computed on the straight-line basis over estimated useful lives of the assets as follows:

Buildings and improvements Useful lives of 40 years for buildings and 15 years for improvements

Furniture and fixtures Useful lives, ranging from five years to 20 years

Tenant improvements Shorter of economic life or lease terms

Purchase Accounting – Upon acquisitions of real estate, the Company assesses the fair value of acquired assets and assumed liabilities (including land, buildings and improvements, and identified intangibles such as above- and below-market leases and acquired in-place leases and customer relationships) and acquired liabilities in accordance with ASC Topic 805, “Business Combinations” and ASC Topic 350 “Intangibles – Goodwill and Other,” and allocates the acquisition price based on these assessments.

The Company assesses fair value of its tangible assets acquired and assumed liabilities based on estimated cash flow projections that utilize appropriate discount and capitalization rates and available market information at the measurement period. Estimates of future cash flows are based on a number of factors including the historical operating results, known trends, and market/economic conditions that may affect the property.

In determining the value of above- and below-market leases, the Company estimates the present value difference between contractual rent obligations and estimated market rate of leases at the time of the transaction. To the extent there were fixed-rate options at below-market rental rates, the Company included these along with the current term below-market rent in arriving at the fair value of the acquired leases. The discounted difference between contract and market rents is being amortized to rental income over the remaining applicable lease term, inclusive of any option periods.

In determining the value of acquired in-place leases and customer relationships, the Company considers market conditions at the time of the transaction and values the costs to execute similar leases during the expected lease-up period from vacancy to existing occupancy, including carrying costs. The value assigned to in-place leases and tenant relationships is amortized over the estimated remaining term of the leases. If a lease were to be terminated prior to its scheduled expiration, all unamortized costs relating to that lease would be written off.

The Company estimates the value of any assumption of mortgage debt based on market conditions at the time of acquisitions including prevailing interest rates, terms and ability to obtain financing for a similar asset. Mortgage debt discounts or premiums are amortized into interest expense over the remaining term of the related debt instrument.

Real Estate Under Development – The Company capitalizes certain costs related to the development of real estate. Interest and real estate taxes incurred during the period of the construction, expansion or development of real estate are capitalized and depreciated over the estimated useful life of the building. The Company will cease the capitalization of these costs when construction activities are substantially completed and the property is available for occupancy by tenants, but no later than one year from the completion of major construction activity at which time the project is placed in service and depreciation commences. If the Company suspends substantially all activities related to development of a qualifying asset, the Company will cease capitalization of interest and taxes until activities are resumed.

Real Estate Impairment – The Company reviews its real estate and real estate under development for impairment when there is an event or a change in circumstances that indicates that the carrying amount may not be recoverable. In cases where the Company does not expect to recover its carrying costs on properties held for use, the Company reduces its carrying costs to fair value. The determination of anticipated undiscounted cash flows is inherently subjective, requiring significant estimates made by management, and considers the most likely expected course of action at the balance sheet date based on current plans, intended holding periods and available market information. If the Company is evaluating the potential sale of an asset, the undiscounted future cash flows analysis is probability-weighted based upon management’s best estimate of the likelihood of the alternative courses of action as of the balance sheet date. Such cash flow projections consider factors such as expected future operating income, trends and prospects, as well as the effects of demand, competition and other factors. If an impairment is indicated, an impairment loss is recognized based on the excess of the carrying amount of the asset over its fair value. See Note 8 for information about impairment charges incurred during the periods presented.

Dispositions of Real Estate – The Company recognizes property sales in accordance with ASC Topic 970 “Real Estate.” Sales of real estate include the sale of land, operating properties and investments in real estate joint ventures. Gains from dispositions are recognized using the full accrual or partial sale methods, provided that various criteria relating to the terms of sale and any subsequent involvement by the Company with the asset sold are met.

Real Estate Held for Sale – The Company generally considers assets to be held for sale when it has entered into a contract to sell the property, all material due diligence requirements have been satisfied, and management believes it is probable that the disposition will occur within one year. Assets that are classified as held for sale are recorded at the lower of their carrying amount or fair value, less cost to sell.

Notes Receivable

Notes receivable include certain loans that are held for investment and are collateralized by real estate-related investments and may be subordinate to other senior loans. Notes receivable are recorded at stated principal amounts or at initial investment less accretive yield for loans purchased at a discount, which is accreted over the life of the note. The Company defers loan origination and commitment fees, net of origination costs, and amortizes them over the term of the related loan. The Company evaluates the collectability of both principal and interest based upon an assessment of the underlying collateral value to determine whether it is impaired. A reserve is recorded when, based upon current information and events, it is probable that the Company will be unable to collect all amounts due according to the existing contractual terms. The amount of the reserve is calculated by comparing the recorded investment to the value of the underlying collateral. As the underlying collateral for a majority of the notes receivable is real estate-related investments, the same valuation techniques are used to value the collateral as those used to determine the fair value of real estate investments for impairment purposes. Given the small number of notes outstanding, the Company does not provide for an additional reserve based on the grouping of loans, as the Company believes the characteristics of its notes are not sufficiently similar to allow an evaluation of these notes as a group for a possible loan loss allowance. As such, all of the Company’s notes are evaluated individually for this purpose. Interest income on performing notes is accrued as earned. A note is placed on non-accrual status when, based upon current information and events, it is probable that the Company will not be able to collect all amounts due according to the existing contractual terms. Recognition of interest income on an accrual basis on non-performing notes is resumed when it is probable that the Company will be able to collect amounts due according to the contractual terms.

Investments in and Advances to Unconsolidated Joint Ventures

Some of the Company’s joint ventures obtain non-recourse third-party financing on their property investments, contractually limiting the Company’s exposure to losses. The Company recognizes income for distributions in excess of its investment where there is no recourse to the Company and no intention or obligation to contribute additional capital. For investments in which there is recourse to the Company or an obligation or intention to contribute additional capital exists, distributions in excess of the investment are recorded as a liability.

When characterizing distributions from equity investees within the Company's consolidated statements of cash flows, all distributions received are first applied as returns on investment to the extent there are cumulative earnings related to the respective investment and are classified as cash inflows from operating activities. If cumulative distributions are in excess of cumulative earnings, distributions are considered return of investment. In such cases, the distribution is classified as cash inflows from investing activities.

To the extent that the Company’s carrying basis in an unconsolidated affiliate is different from the basis reflected at the joint venture level, the basis difference is amortized over the life of the related assets and included in the Company’s share of equity in net income (loss) of investments in unconsolidated affiliates the joint venture.

The Company periodically reviews its investments in unconsolidated joint ventures for other-than-temporary losses in investment value. Any decline that is not expected to be recovered based on the underlying assets of the investment, is considered other than temporary and an impairment charge is recorded as a reduction in the carrying value of the investment. During the periods presented there were no impairment charges related to the Company’s investments in unconsolidated joint ventures.

Cash and Cash Equivalents

The Company considers all highly liquid investments with an original maturity of three months or less when purchased to be cash equivalents. Cash and cash equivalents are maintained at financial institutions and, at times, balances may exceed the limits insured by the Federal Deposit Insurance Corporation.

Restricted Cash

Restricted cash consists principally of cash held for real estate taxes, construction costs, property maintenance, insurance, minimum occupancy and property operating income requirements at specific properties as required by certain loan agreements.

Deferred Costs

Fees and costs paid in the successful negotiation of leases are deferred and amortized on a straight-line basis over the terms of the respective leases. Fees and costs incurred in connection with obtaining financing are deferred and amortized as a component of interest expense over the term of the related debt obligation on a straight-line basis, which approximates the effective interest method. The Company capitalizes salaries, commissions and benefits related to time spent by leasing and legal department personnel involved in originating leases.

Derivative Instruments and Hedging Activities

The Company measures derivative instruments at fair value and records them as assets or liabilities, depending on its rights or obligations under the applicable derivative contract. Derivatives that are not designated as hedges must be adjusted to fair value through earnings. For a derivative designated and that qualified as a cash flow hedge, the effective portion of the change in fair value of the derivative is recognized in Other comprehensive (loss) income until the hedged item is recognized in earnings. The ineffective portion of a derivative’s change in fair value is immediately recognized in earnings.

Although the Company's derivative contracts are subject to master netting arrangements, which serve as credit mitigants to both the Company and its counterparties under certain situations, the Company does not net its derivative fair values or any existing rights or obligations to cash collateral on the consolidated balance sheets. The Company does not use derivatives for trading or speculative purposes. For the periods presented, all of the Company's derivatives qualified and were designated as cash flow hedges, and none of its derivatives were deemed ineffective.

Noncontrolling Interests

Noncontrolling interests represent the portion of equity that the Company does not own in those entities it consolidates. The Company identifies its noncontrolling interests separately within the equity section on the Company’s consolidated balance sheets. The amounts of consolidated net earnings attributable to the Company and to the noncontrolling interests are presented separately on the Company’s consolidated statements of income. Noncontrolling interests also include amounts related to common and preferred OP Units issued to unrelated third parties in connection with certain property acquisitions. In addition, the Company periodically issues common OP Units to certain employees of the Company under its share-based incentive program. Unit holders generally have the right to redeem their units for shares of the Company's common stock subject to blackout and other limitations. Common and restricted OP Units are included in the caption Noncontrolling interest within the equity section on the Company’s consolidated balance sheets.

Revenue Recognition and Accounts Receivable

Minimum rents from tenants are recognized using the straight-line method over the non-cancelable lease term of the respective leases. Lease termination fees are recognized upon the effective termination of a tenant’s lease when the Company has no further obligations under the lease. As of December 31, 2017 and 2016, unbilled rents receivable relating to the straight-lining of rents of $37.3 million and $34.9 million, respectively, are included in Rents Receivable, net on the accompanying consolidated balance sheets. Certain of these leases also provide for percentage rents based upon the level of sales achieved by the tenant. Percentage rent is recognized in the period when the tenants’ sales breakpoint is met. In addition, leases typically provide for the reimbursement to the Company of real estate taxes, insurance and other property operating expenses. These reimbursements are recognized as revenue in the period the related expenses are incurred.

The Company makes estimates of the uncollectability of its accounts receivable related to tenant revenues. An allowance for doubtful accounts has been provided against certain tenant accounts receivable that are estimated to be uncollectible. Once the amount is ultimately deemed to be uncollectible, it is written off. Rents receivable at December 31, 2017 and 2016 are shown net of an allowance for doubtful accounts of $5.9 million and $5.7 million, respectively.

Stock-Based Compensation

Stock-based compensation expense for all equity-classified stock-based compensation awards is based on the grant date fair value estimated in accordance with current accounting guidance for share-based payments. The Company recognizes these compensation costs for only those shares or units expected to vest on a straight-line or graded-vesting basis, as appropriate, over the requisite service period of the award. The Company includes stock-based compensation within the Additional paid-in capital caption of equity.

Income Taxes

The Company has made an election to be taxed, and believes it qualifies, as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended (the “Code”). To maintain REIT status for Federal income tax purposes, the Company is generally required to distribute at least 90% of its REIT taxable income to its shareholders as well as comply with certain other income, asset and organizational requirements as defined in the Code. Accordingly, the Company is generally not subject to Federal corporate income tax to the extent that it distributes 100% of its REIT taxable income each year.

In connection with the REIT Modernization Act, the Company is permitted to participate in certain activities and still maintain its qualification as a REIT, so long as these activities are conducted in entities that elect to be treated as taxable subsidiaries under the Code. As such, the Company is subject to Federal and state income taxes on the income from these activities. The Protecting Americans from Tax Hikes Act (PATH Act) was enacted in December 2015, and included numerous law changes applicable to REITs. The provisions have various effective dates beginning as early as 2016. These changes did not materially impact the Company's operations or consolidated financial statements.

The Tax Cuts and Jobs Act was enacted in December 2017 and is generally effective for tax years beginning in 2018. This new legislation is not expected to have a material adverse effect on the Company’s business and contains several potentially favorable provisions. However, the Company has recorded an reduction of $2.0 million to its deferred tax assets to reflect the lower Federal corporate tax rate and other provisions effective in 2018.

Although it may qualify for REIT status for Federal income tax purposes, the Company is subject to state income or franchise taxes in certain states in which some of its properties are located. In addition, taxable income from non-REIT activities managed through the Company’s taxable REIT subsidiaries (“TRS”) is fully subject to Federal, state and local income taxes.

The Company accounts for TRS income taxes under the liability method as required by ASC Topic 740, “Income Taxes.” Under the liability method, deferred income taxes are recognized for the temporary differences between the GAAP basis and tax basis of the TRS income, assets and liabilities.

The Company records net deferred tax assets to the extent it believes it is more likely than not that these assets will be realized and would record a valuation allowance to reduce deferred tax assets when it has determined that an uncertainty exists regarding their realization, which would increase the provision for income taxes. In making such determination, the Company considers all available positive and negative evidence, including forecasts of future taxable income, the reversal of other existing temporary differences, available net operating loss carry-forwards, tax planning strategies and recent results of operations. Several of these considerations require assumptions and significant judgment about the forecasts of future taxable income and are consistent with the plans and estimates that the Company is utilizing to manage its business. To the extent facts and circumstances change in the future, adjustments to the valuation allowances may be required.

Recently Issued Accounting Pronouncements

In May 2014, the FASB issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers. ASU 2014-09 is a comprehensive new revenue recognition model requiring a company to recognize revenue to depict the transfer of goods or services to a customer at an amount reflecting the consideration it expects to receive in exchange for those goods or services. ASU 2014-09 does not apply to the Company’s lease revenues, but will apply to reimbursed tenant costs. Additionally, this guidance modifies disclosures regarding the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. In August 2015, the FASB issued ASU 2015-14, which defers the effective date of ASU 2014-09 for all entities by one year, until years beginning in 2018, with early adoption permitted but not before 2017. Entities may adopt ASU 2014-09 using either a full retrospective approach reflecting the application of the standard in each prior reporting period with the option to elect certain practical expedients or a modified retrospective approach with the cumulative effect recognized at the date of adoption. Substantially all of the Company’s revenue is derived from its leases and therefore falls outside of the scope of this guidance. With respect to its fee-derived revenue, the Company does not anticipate any significant changes to the timing of the Company’s revenue recognition; however, the recognition of gains on sales of properties may be impacted prospectively under limited circumstances under which collectability may not be reasonably assured or if the Company has continuing involvement with a sold property. The Company intends to implement the standard using the modified retrospective approach with the cumulative effect recognized in retained earnings at the date of application.

In February 2016, the FASB issued ASU No. 2016-02, Leases. ASU 2016-02 outlines a new model for accounting by lessees, whereby their rights and obligations under substantially all leases, existing and new, would be capitalized and recorded on the balance sheet. As a lessee, the Company is party to various equipment, ground, and office leases with future payment obligations aggregating $207.2 million at December 31, 2017 (Note 11) for which the Company expects to record right-of-use assets upon adoption of ASU 2016-02. For lessors, however, the accounting remains largely unchanged from the current model, with the distinction between operating and financing leases retained, but updated to align with certain changes to the lessee model and the new revenue recognition standard discussed above. The new guidance also requires that internal leasing costs be expensed as incurred, as opposed to capitalized and deferred. The Company expects that it will no longer capitalize a significant portion of internal leasing costs that were previously capitalized. The Company capitalized $1.0 million, $1.1 million and $1.4 million of internal leasing costs during the years ended December 31, 2017, 2016 and 2015, respectively. ASU 2016-02 will also require extensive quantitative and qualitative disclosures and is effective beginning after December 15, 2018, but early adoption is permitted.

In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments – Credit Losses. ASU 2016-13 introduces a new model for estimating credit losses for certain types of financial instruments, including loans receivable, held-to-maturity debt securities, and net investments in direct financing leases, amongst other financial instruments. ASU 2016-13 also modifies the impairment model for available-for-sale debt securities and expands the disclosure requirements regarding an entity’s assumptions, models, and methods for estimating the allowance for losses. ASU 2016-13 is effective for periods beginning after December 15, 2019, with adoption permitted for fiscal years beginning after December 15, 2018. Retrospective adjustments shall be applied through a cumulative-effect adjustment to retained earnings. The adoption of ASU 2016-13 is not expected to have a material impact on the Company’s consolidated financial statements.

In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows – Classification of Certain Cash Receipts and Cash Payments. ASU 2016-15 provides guidance on certain specific cash flow issues, including, but not limited to, debt prepayment or extinguishment costs, contingent consideration payments made after a business combination and distributions received from equity method investees. ASU 2016-15 is effective for periods beginning after December 15, 2017, with early adoption permitted and shall be applied retrospectively where practicable. The Company expects to elect the “cumulative distribution approach” whereby distributions received from equity method investments would be classified as cash flows from operations to the extent of equity earnings and then as cash flows from investing activities thereafter. Upon the adoption of ASU 2016-15, the Company expects to reclassify $6.3 million and $0 of its cash inflows from investing activities to cash flows from operating activities in its historical presentation of cash flows related to its equity method investments for the years ended December 31, 2017 and 2016, respectively.

In January 2017, the FASB issued ASU No. 2017-01, Business Combinations – Clarifying the Definition of a Business. ASU 2017-01 clarifies that to be considered a business, the elements must include, at a minimum, an input and a substantive process that together significantly contribute to the ability to create output. The new standard illustrates the circumstances under which real estate with in-place leases would be considered a business and provides guidance for the identification of assets and liabilities in purchase accounting. ASU 2017-01 is effective for periods beginning after December 15, 2017 and early adoption is permitted. It is expected that the new standard will reduce the number of future real estate acquisitions that will be accounted for as business combinations and, therefore, reduce the amount of acquisition costs that will be expensed. The Company expensed $2.1 million and $8.2 million of acquisition costs during the year ended December 31, 2017 and 2016, respectively.

In January 2017, the FASB issued ASU No. 2017-03 Accounting Changes and Error Corrections (Topic 250) and Investments – Equity Method and Joint Ventures (Topic 323). ASU 2017-03 amends certain SEC guidance in the FASB Accounting Standards Codification in response to SEC staff announcements made during 2016 Emerging Issues Task Force (“EITF”) meetings which addressed (i) the additional qualitative disclosures that a registrant is expected to provide when it cannot reasonably estimate the impact that ASUs 2014-09, 2016-02 and 2016-13 will have in applying the guidance in Staff Accounting Bulletin Topic 11.M and (ii) guidance in ASC 323 related to the amendments made by ASU 2014-01 regarding use of the proportional amortization method in accounting for investments in qualified affordable housing projects (announcement made at the November 17, 2016, EITF meeting). The adoption of ASU 2017-03 is not expected to have a material impact on the Company’s consolidated financial statements.

In February 2017, the FASB issued ASU 2017-05, Other Income—Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20): Clarifying the Scope of Asset Derecognition Guidance and Accounting for Partial Sales of Nonfinancial Assets, which amends the guidance on nonfinancial assets in ASC 610-20. The amendments clarify that (i) a financial asset is within the scope of ASC 610-20 if it meets the definition of an in substance nonfinancial asset and may include nonfinancial assets transferred within a legal entity to a counter-party, (ii) an entity should identify each distinct nonfinancial asset or in substance nonfinancial asset promised to a counter-party and de-recognize each asset when a counter-party obtains control of it, and (iii) an entity should allocate consideration to each distinct asset by applying the guidance in ASC 606 on allocating the transaction price to performance obligations. Further, ASU 2017-05 provides guidance on accounting for partial sales of nonfinancial assets. The amendments are effective at the same time as the amendments in ASU 2014-09. The adoption of ASU 2017-05 is not expected to have a material impact on the Company's consolidated financial statements.

In May 2017, the FASB issued ASU 2017-09, Compensation—Stock Compensation (Topic 718): Scope of Modification Accounting, which clarifies the scope of modification accounting with respect to changes to the terms or conditions of a share-based payment award. Modification accounting would not apply if a change to an award does not affect the total current fair value (or other applicable measurement), vesting conditions, or the classification of the award. For all entities, ASU 2017-09 is effective prospectively for awards modified in fiscal years beginning after December 15, 2017, and interim periods within those annual periods and early adoption is permitted. The adoption of ASU 2017-09 is not expected to have a material impact on the Company's consolidated financial statements because the Company has not historically had significant modifications of its awards.

In August 2017, the Financial Accounting Standards Board issued ASU 2017-12, Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities. The purpose of this updated guidance is to better align a company’s financial reporting for hedging activities with the economic objectives of those activities. ASU 2017-12 is effective for fiscal years beginning after December 15, 2018, with early adoption, including adoption in an interim period, permitted. The Company plans to adopt ASU 2017-12 effective January 1, 2018. ASU 2017-12 requires a modified retrospective transition method in which the Company will recognize the cumulative effect of the change on the opening balance of each affected component of equity in the statement of financial position as of the date of adoption. The adoption will not have a material impact on the Company’s consolidated financial statements.

Real Estate

12 Months Ended

Dec. 31, 2017

Acquisition and Disposition of Properties and Discontinued Operations [Abstract]

Real Estate

The Company’s consolidated real estate is comprised of the following (in thousands):



	December 31, 2017			December 31, 2016

Land	$	658,835		$	693,252
Buildings and improvements	2,406,488			1,916,288
Tenant improvements	131,850			132,220
Construction in progress	18,642			19,789
Properties under capital lease	76,965			76,965
Total	3,292,780			2,838,514
Less: Accumulated depreciation	(339,862		)	(287,066		)
Operating real estate, net	2,952,918			2,551,448
Real estate under development, at cost	173,702			543,486
Net investments in real estate	$	3,126,620		$	3,094,934

Acquisitions and Conversions

During the years ended December 31, 2017 and December 31, 2016, the Company acquired the following consolidated retail properties (dollars in thousands):



Property and Location	Percent Acquired	Date of Acquisition	Purchase Price		Debt Assumed
2017 Acquisitions and Conversions
Core
Market Square Shopping Center - Wilmington, DE (Conversion) (Note 4)	100%	Nov 16, 2017	$	42,800	$	—
Subtotal Core			42,800		—

Fund IV
Lincoln Place - Fairview Heights, IL	100%	Mar 13, 2017	35,350		—
Shaw's Plaza - Windham, ME (Conversion) (Note 3)	100%	Jun 30, 2017	9,142		—
Subtotal Fund IV			44,492		—

Fund V
Plaza Santa Fe - Santa Fe, NM	100%	Jun 5, 2017	35,220		—
Hickory Ridge - Hickory, NC	100%	Jul 27, 2017	44,020		—
New Towne Plaza - Canton, MI	100%	Aug 4, 2017	26,000		—
Fairlane Green - Allen Park, MI	100%	Dec 20, 2017	62,000		—
Subtotal Fund V			167,240		—
Total 2017 Acquisitions and Conversions			$	254,532	$	—

2016 Acquisitions
Core Portfolio
991 Madison Avenue - New York, NY ^(a)	100%	Mar 26, 2016	$	76,628	$	—
165 Newbury Street - Boston, MA	100%	May 13, 2016	6,250		—
Concord & Milwaukee - Chicago, IL	100%	Jul 28, 2016	6,000		2,902
151 North State Street - Chicago, IL	100%	Aug 10, 2016	30,500		14,556
State & Washington - Chicago, IL	100%	Aug 22, 2016	70,250		25,650
North & Kingsbury - Chicago, IL	100%	Aug 29, 2016	34,000		13,409
Sullivan Center - Chicago, IL	100%	Aug 31, 2016	146,939		—
California & Armitage - Chicago, IL	100%	Sep 12, 2016	9,250		2,692
555 9th Street - San Francisco, CA	100%	Nov 2, 2016	139,775		60,000
Subtotal Core Portfolio			519,592		119,209

Fund IV
Restaurants at Fort Point - Boston, MA	100%	Jan 14, 2016	11,500		—
1964 Union Street - San Francisco, CA^(a)	90%	Jan 28, 2016	2,250		1,463
Wake Forest Crossing - Wake Forest, NC	100%	Sep 27, 2016	36,600		—
Airport Mall - Bangor, ME	100%	Oct 28, 2016	10,250		—
Colonie Plaza - Albany, NY	100%	Oct 28, 2016	15,000		—
Dauphin Plaza - Harrisburg, PA	100%	Oct 28, 2016	16,000		—
JFK Plaza - Waterville, ME	100%	Oct 28, 2016	6,500		—
Mayfair Shopping Center - Philadelphia, PA	100%	Oct 28, 2016	16,600		—
Shaw's Plaza - Waterville, ME	100%	Oct 28, 2016	13,800		—
Wells Plaza - Wells, ME	100%	Oct 28, 2016	5,250		—
717 N Michigan - Chicago, IL	100%	Dec 1, 2016	103,500		—
Subtotal Fund IV			237,250		1,463
Total 2016 Acquisitions			$	756,842	$	120,672

__________


(a)	These acquisitions were accounted for as asset acquisitions as the underlying properties did not meet the definition of a business.

All of the above acquisitions and conversions were deemed to be business combinations except 991 Madison Avenue and 1964 Union Street. The Company expensed $2.1 million of acquisition costs for the year ended December 31, 2017, of which $1.2 million related to the Core Portfolio and $0.9 million related to the Funds and $8.2 million of acquisition costs for the year ended December 31, 2016, of which $5.5 million related to the Core Portfolio and $2.7 million related to the Funds.

Revenues, net loss and loss per share from the Company’s consolidated 2017 acquisitions and conversions totaled $10.2 million, $3.5 million and $0.04, respectively for the year ended December 31, 2017. Revenues, net loss and loss per share from the Company’s consolidated 2016 acquisitions totaled $15.3 million, $4.7 million and $0.06, respectively for the year ended December 31, 2016.

Purchase Price Allocations

The purchase prices for the business combinations were allocated to the acquired assets and assumed liabilities based on their estimated fair values at the dates of acquisition. The following table summarizes the allocation of the purchase price of properties acquired during the years ended December 31, 2017 and December 31, 2016 (in thousands):



	Year Ended December 31, 2017			Year Ended December 31, 2016
	Year Ended December 31, 2017			Year Ended December 31, 2016
Net Assets Acquired
Land	$	48,138		$	225,729
Buildings and improvements	173,576			458,525
Other assets	84			3,481
Acquisition-related intangible assets (in Acquired lease intangibles, net)	44,269			63,606
Acquisition-related intangible liabilities (in Acquired lease intangibles, net)	(11,535		)	(72,985		)
Above and below market debt assumed (included in Mortgages and other notes payable, net)	—			(119,601		)
Net assets acquired	$	254,532		$	558,755



Consideration
Cash	$	200,429	$	439,546
Conversion of note receivable	41,010		—
Debt assumed	—		119,209
Liabilities assumed	3,363		—
Existing interest in previously unconsolidated investment	4,159		—
Change in control of previously unconsolidated investment	5,571		—
Total Consideration	$	254,532	$	558,755

Dispositions

During the years ended December 31, 2017 and December 31, 2016, the Company disposed of the following consolidated properties (in thousands):



Property and Location	Owner	Date Sold	Sale Price		Gain/(Loss) on Sale
2017 Dispositions
New Hyde Park Shopping Center - New Hyde Park, NY	Fund III	Jul 6, 2017	$	22,075	$	6,433
216th Street - New York, NY	Fund II	Sep 11, 2017	30,579		6,543
City Point Condominium Tower I - Brooklyn, NY	Fund II	Oct 13, 2017	96,000		(810		)
1151 Third Avenue - New York, NY	Fund IV	Nov 16, 2017	27,000		5,183
260 E 161st Street - Bronx, NY	Fund II	Dec 13, 2017	105,684		31,537
Total 2017 Dispositions			$	281,338	$	48,886

2016 Dispositions
Cortlandt Town Center (65%) - Mohegan Lake, NY (Note 4)	Fund III	Jan 28, 2016	$	107,250	$	65,393
Heritage Shops - Chicago, IL	Fund III	Apr 26, 2016	46,500		16,572
Total 2016 Dispositions			$	153,750	$	81,965

The Company has recognized impairment charges during the periods presented related to certain properties classified as held for sale and or sold (Note 8).

The aggregate rental revenue, expenses and pre-tax income reported within continuing operations for the aforementioned consolidated properties that were sold during the years ended December 31, 2017, 2016 and 2015 were as follows (in thousands):



	Year Ended December 31,
	2017			2016			2015
Rental revenues	$	13,021		$	16,946		$	31,935
Expenses	(18,964		)	(13,653		)	(27,265		)
Loss on extinguishment of debt	(1,380		)	(81		)	(111		)
(Loss) income from continuing operations of disposed properties before gain on disposition of properties	(7,323		)	3,212			4,559
Gain on disposition of properties, net of tax	48,886			81,965			89,063
Net income attributable to noncontrolling interests	(30,072		)	(70,850		)	(1,732		)
Net income attributable to Acadia	$	11,491		$	14,327		$	91,890

Properties Held For Sale

At December 31, 2017, the Company had one property in Fund II classified as held-for-sale, Sherman Avenue, with total assets of $25.4 million and recognized an impairment charge of $10.6 million inclusive of an amount attributable to a noncontrolling interest of $7.6 million (Note 8). This property had a net loss of $12.0 million and $0.8 million and $0.0 for the years ended December 31, 2017, 2016, and 2015, respectively. At December 31, 2015, the property was under development.

At December 31, 2016, the Company had one property in Fund II classified as held-for-sale with total assets of $21.5 million and subject to a mortgage of $25.5 million.

Pro Forma Financial Information (Unaudited)

The following unaudited pro forma consolidated operating data is presented for the year ended December 31, 2017, as if the acquisitions of the properties acquired during that period were completed on January 1, 2016 and as if the acquisition of the properties acquired during the year ended December 31, 2016 were completed on January 1, 2015. The related acquisition expenses of $2.1 million and $8.2 million reported during the years ended December 31, 2017 and 2016, respectively have been reflected as pro forma charges at January 1, 2016 and January 1, 2015, respectively. The unaudited supplemental pro forma operating data is not necessarily indicative of what the actual results of operations of the Company would have been, assuming the transactions had been completed as set forth above, nor do they purport to represent the Company’s results of operations for future periods.



	Year Ended December 31,
	2017		2016		2015
Pro forma revenues	$	266,485	$	247,843	$	243,237
Pro forma income from continuing operations	21,878		63,681		52,442
Pro forma net income attributable to Acadia	64,107		82,485		58,232
Pro forma basic and diluted earnings per share	0.77		1.02		0.79

Real Estate Under Development and Construction in Progress

Real estate under development represents the Company’s consolidated properties that have not yet been placed into service while undergoing substantial development or construction.

Depreciation and amortization expense for the year ended December 31, 2017 includes $2.0 million of accelerated depreciation related to a building under development that was demolished.

Development activity for the Company’s consolidated properties comprised the following during the periods presented (dollars in thousands):



	December 31, 2016			Year Ended December 31, 2017						December 31, 2017
	Number of Properties	Carrying Value		Transfers In		Capitalized Costs		Transfers Out		Number of Properties	Carrying Value
Core	1	$	3,499	$	22,422	$	819	$	4,843	2	$	21,897
Fund II	2	443,012		—		6,851		444,955		—	4,908
Fund III	3	50,452		—		22,572		9,085		2	63,939
Fund IV	4	46,523		80,508		2,158		46,231		1	82,958
Total	10	$	543,486	$	102,930	$	32,400	$	505,114	5	$	173,702

During the year ended December 31, 2017, the Company placed substantially all of Fund II’s City Point project into service as well as three Fund IV properties, reclassified Fund II’s Sherman Avenue property as held for sale and placed one Core property into development. In addition to the consolidated projects noted above, the Company had one unconsolidated project remaining in development after placing three of its four unconsolidated Fund IV development properties into service during the year ended December 31, 2017.

Construction in progress pertains to construction activity at the Company’s operating properties which are in service and continue to operate during the construction period.

Notes Receivable, Net

12 Months Ended

Dec. 31, 2017

Accounts and Notes Receivable, Net [Abstract]

Notes Receivable, Net

The Company’s notes receivable, net were collateralized either by the underlying properties or the borrower’s ownership interest in the entities that own the properties, and were as follows (dollars in thousands):



	December 31,		December 31,		December 31, 2017
Description	2017		2016		Number	Maturity Date	Interest Rate
Core Portfolio	$	101,695	$	216,400	3	June 2018 - April 2019	6.0% - 8.1%
Fund II	31,778		31,007		1	May 2020	2.5%
Fund III	5,106		4,506		1	July 2020	18.0%
Fund IV	15,250		24,250		1	February 2021	15.3%
	$	153,829	$	276,163	6

During the year ended December 31, 2017, the Company:


•	recovered the full value of a $12.0 million Core note receivable, which was previously in default, plus accrued interest and fees aggregating $16.8 million as further described below;


•	exchanged $92.7 million of Core notes receivable plus accrued interest thereon of $1.8 million for additional undivided interests in the Market Square and Town Center properties (Note 4);


•	funded an additional $10.0 million on an existing Core note receivable, which had a total commitment of $20.0 million, and was subsequently repaid in full during the fourth quarter;


•	entered into an agreement to extend the maturity of a $15.0 million Core note receivable to June 1, 2018;


•	increased the balance of a Fund II note receivable by the interest accrued of $0.8 million;


•	advanced an additional $0.6 million on a Fund III note receivable; and


•	exchanged a $9.0 million Fund IV note receivable plus accrued interest of $0.1 million thereon for an investment in a shopping center in Windham, Maine (Note 2).

During the year ended December 31, 2016, the Company:


•	issued one Core note receivable and three Fund IV notes receivable aggregating $47.5 million with a weighted-average effective interest rate of 9.8%, which were collateralized by four mixed-use real estate properties;


•	received total collections of $42.8 million, including full repayment of five notes issued in prior periods aggregating $29.6 million; and


•	restructured a $30.9 million Core mezzanine loan, which bore interest at 15.0%, and replaced it with a new $153.4 million loan collateralized by a first mortgage in the borrower’s tenancy-in-common interest. The loan bears interest at 8.1% (Note 4).

At December 31, 2016, one of the Core notes receivable in the amount of $12.0 million was in default. As discussed above, the Company recovered its full carrying value of principal and interest and recognized additional interest income and expense reimbursements of $2.2 million in the first quarter of 2017 and $1.4 million in the second quarter of 2017 upon settlement of this transaction.

The Company monitors the credit quality of its notes receivable on an ongoing basis and considers indicators of credit quality such as loan payment activity, the estimated fair value of the underlying collateral, the seniority of the Company’s loan in relation to other debt secured by the collateral and the prospects of the borrower.

Earnings from these notes and mortgages receivable are reported within the Company’s Structured Financing segment (Note 12).

- Definition

The entire disclosure for claims held for amounts due a entity, excluding financing receivables. Examples include, but are not limited to, trade accounts receivables, notes receivables, loans receivables. Includes disclosure for allowance for credit losses.

+ References + Details

Investments in and Advances to Unconsolidated Affiliates

12 Months Ended

Dec. 31, 2017

Equity Method Investments and Joint Ventures [Abstract]

Investments in and Advances to Unconsolidated Affiliates

Investments In and Advances to Unconsolidated Affiliates

The Company accounts for its investments in and advances to unconsolidated affiliates primarily under the equity method of accounting as it has the ability to exercise significant influence, but does not have financial or operating control over the investment, which is maintained by each of the unaffiliated partners who co-invest with the Company. The Company’s investments in and advances to unconsolidated affiliates consist of the following (dollars in thousands):



		Nominal Ownership Interest	December 31, 2017		December 31, 2016
Fund	Property	December 31, 2017	December 31, 2017		December 31, 2016
Core:
	840 N. Michigan ^(a)	88.43%	$	69,846	$	74,131
	Renaissance Portfolio	20%	35,041		36,437
	Gotham Plaza	49%	29,416		29,421
	Market Square ^{(a, b)}	100%	—		5,469
	Town Center ^{(a, b)}	61.11%	78,801		15,286
	Georgetown Portfolio	50%	3,479		4,287
			216,583		165,031

Mervyns I & II:	KLA/Mervyn's, LLC^(c)	10.5%	—		—

Fund III:
	Fund III Other Portfolio	90%	167		8,108
	Self Storage Management ^(d)	95%	206		241
			373		8,349
Fund IV:
	Broughton Street Portfolio ^(e)	50%	48,335		54,839
	Fund IV Other Portfolio	90%	20,199		21,817
	650 Bald Hill Road	90%	13,609		18,842
			82,143		95,498

Various Funds:	Due from Related Parties ^(f)		2,415		2,193
	Other^(g)		556		957
	Investments in and advances to unconsolidated affiliates		$	302,070	$	272,028

Core:
	Crossroads ^(h)	49%	$	15,292	$	13,691
	Distributions in excess of income from, and investments in, unconsolidated affiliates		$	15,292	$	13,691

__________


(a)	Represents a tenancy-in-common interest.


(b)	During May and November 2017, as discussed below, the Company increased its ownership in Market Square and Town Center, which was formerly included under the caption “Brandywine Portfolio.”


(c)	Distributions have exceeded the Company’s non-recourse investment, therefore the carrying value is zero.


(d)	Represents a variable interest entity.


(e)	The Company is entitled to a 15% return on its cumulative capital contribution which was $15.4 million and $14.5 million at December 31, 2017 and December 31, 2016, respectively. In addition, the Company is entitled to a 9% preferred return on a portion of its equity, which was $36.8 million and $45.4 million at December 31, 2017 and December 31, 2016, respectively.


(f)	Represents deferred fees.


(g)	Includes a cost-method investment in Albertson’s (Note 8) and other investments.


(h)	Distributions have exceeded the Company’s investment; however, the Company recognizes a liability balance as it may be required to fund future obligations of the entity.

Core Portfolio

The Company owns a 49% interest in a 311,000 square foot shopping center located in White Plains, New York (“Crossroads”), a 50% interest in a 28,000 square foot retail portfolio located in Georgetown, Washington D.C. (the “Georgetown Portfolio”), an 88.43% tenancy-in-common interest in an 87,000 square foot retail property located in Chicago, Illinois (“840 N. Michigan”), and a 49% interest in an approximately 123,000 square foot retail property located in Manhattan, New York (“Gotham Plaza”).

Acquisition of Unconsolidated Investment

On January 4, 2017, an entity in which the Company owns a 20% noncontrolling interest (the “Renaissance Portfolio”), acquired a 6,200 square foot property in Alexandria, Virginia referred to as (“907 King Street”) for $3.0 million. The Renaissance Portfolio is now a 213,000 square-foot portfolio of 18 mixed-use properties, 16 of which are located in Georgetown, Washington D.C. and two of which are located in Alexandria, Virginia.

Brandywine Portfolio, Market Square and Town Center

The Company owns an interest in an approximately one million square foot retail portfolio (the “Brandywine Portfolio” joint venture) located in Wilmington, Delaware, which includes two properties referred to as “Market Square” and “Town Center.” Prior to the second quarter of 2016, the Company had a controlling interest in the Brandywine Portfolio, and it was therefore consolidated within the Company’s financial statements. During April 2016, the arrangement with the partners of the Brandywine Portfolio was modified to change the legal ownership from a partnership to a tenancy-in-common interest, as well as to provide certain participating rights to the outside partners. As a result of these modifications, the Company de-consolidated the Brandywine Portfolio and accounted for its interest under the equity method of accounting effective May 1, 2016. Furthermore, as the owners of the Brandywine Portfolio had consistent ownership interests before and after the modification and the underlying net assets were unchanged, the Company reflected the change from consolidation to equity method based upon its historical cost. The Brandywine Portfolio and Market Square ventures do not include the property held by Brandywine Holdings, an entity consolidated by the Company.

Additionally, in April 2016, the Company repaid the outstanding balance of $140.0 million of non-recourse debt collateralized by the Brandywine Portfolio and provided a note receivable collateralized by the partners’ tenancy-in-common interest in the Brandywine Portfolio for their proportionate share of the repayment. On May 1, 2017, the Company exchanged $16.0 million of the $153.4 million notes receivable (the “Brandywine Notes Receivable”) (Note 3) plus accrued interest of $0.3 million for one of the partner’s 38.89% tenancy-in-common interests in Market Square. The Company already had a 22.22% interest in Market Square and continued to apply the equity method of accounting for its aggregate 61.11% noncontrolling interest in Market Square and its 22.22% interest in Town Center through November 16, 2017. The incremental investment in Market Square was recorded at $16.3 million and the excess of this amount over the venture’s book value associated with this interest, or $9.8 million, was being amortized over the remaining depreciable lives of the venture’s assets through November 16, 2017. On November 16, 2017, the Company exchanged an additional $16.0 million of Brandywine Notes Receivable plus accrued interest of $0.6 million for the remaining 38.89% interest in Market Square, thereby obtaining a 100% controlling interest in the property. The exchange was deemed to be a business combination and as a result, the property was consolidated and a gain on change of control of $5.6 million was recorded (Note 2).

On November 16, 2017, the Company exchanged $60.7 million of the Brandywine Notes Receivable plus accrued interest of $0.9 million for one of the partner’s 38.89% tenancy-in-common interests in Town Center. The incremental investment in Town Center was recorded at $61.6 million and the excess of this amount over the venture’s book value associated with this interest, or $34.5 million, will be amortized over the remaining depreciable lives of the venture’s assets. The Company already had a 22.22% interest in Town Center and continues to apply the equity method of accounting for its aggregate 61.11% noncontrolling interest in Town Center.

At December 31, 2017, a $60.7 million of Brandywine Note Receivable remains (Note 3), which is collateralized by the remaining 38.89% undivided interest in Town Center.

Fund Investments

Fund III Other Portfolio includes the Company’s investment in Arundel Plaza (through its date of sale). Fund IV Other Portfolio includes the Company’s investment in Promenade at Manassas, Eden Square, 2819 Kennedy Boulevard (through its date of sale) and 1701 Belmont Avenue (through its date of sale). Self-Storage Management, a Fund III investment, was determined to be a variable interest entity. Management has evaluated the applicability of ASC Topic 810 to this joint venture and determined that the Company is not the primary beneficiary and, therefore, consolidation of this venture is not required.

Mervyn’s I & II

In 2017, Mervyn’s I and Mervyn’s II received a total of $1.1 million in distributions from certain investments. The Company had already reduced the carrying amount of its investments in Mervyn’s I and Mervyn’s II to zero, and consequently the entire amount received has been reflected as equity in earnings and gains of unconsolidated affiliates in the consolidated statements of income.

Albertson’s

“Other” includes Fund II’s cost method investment in Albertson’s supermarkets among other investments. In 2017, the Company received $2.4 million in distributions from Albertson’s. The Company reduced the carrying amount of the investment to zero and reflected the remaining $2.0 million as equity in earnings and gains of unconsolidated affiliates in the consolidated statements of income.

Dispositions of Unconsolidated Investments

On January 31, 2017, Fund IV completed the disposition of 2819 Kennedy Boulevard, for $19.0 million less $8.4 million debt repayment for net proceeds of $10.6 million, resulting in a gain on disposition of $6.3 million at the property level, of which the Fund’s share was $6.2 million, which is included in equity in earnings and gains from unconsolidated affiliates in the consolidated statements of income. The Operating Partnership’s proportionate share of the gain was $1.4 million, net of noncontrolling interests.

On February 15, 2017, Fund III completed the disposition of Arundel Plaza, for $28.8 million less $10.0 million debt repayments for net proceeds of $18.8 million, resulting in a gain on disposition of $8.2 million at the property level, of which the Fund’s share was $5.3 million, which is included in equity in earnings and gains from unconsolidated affiliates in the consolidated statements of income. The Operating Partnership’s proportionate share of the gain was $1.3 million, net of noncontrolling interests.

On June 30, 2017, Fund IV completed the disposition of 1701 Belmont Avenue, for $5.6 million less $2.9 million debt repayments for net proceeds of $2.7 million, resulting in a gain on disposition of $3.3 million at the property level, of which the Fund’s share was $3.3 million, which is included in equity in earnings and gains from unconsolidated affiliates in the consolidated statements of income. The Operating Partnership’s proportionate share of the gain was $0.8 million, net of noncontrolling interests.

On October 3 and December 21, 2017, Fund IV’s Broughton Street Portfolio venture sold a total of five properties for aggregate proceeds of $11.0 million resulting in a net gain of $1.2 million at the property level, of which the Fund’s share was $0.6 million, which is included in equity in earnings and gains from unconsolidated affiliates in the consolidated financial statements. The Operating Partnership’s proportionate share of the gain was $0.1 million, net of noncontrolling interests. At December 31, 2017, the Broughton Street portfolio had 18 remaining properties; however, during January 2018, two additional Broughton Street Portfolio properties were sold (Note 17).

On January 28, 2016, Fund III completed the disposition of a 65% interest in Cortlandt Town Center for $107.3 million resulting in a gain of $65.4 million and the deconsolidation of its remaining interest (Note 2). On December 21, 2016, Fund III completed the disposition of its remaining 35% interest in Cortlandt Town Center for $57.8 million less $32.6 million debt repayment for a net sales price of $25.2 million resulting in a gain on sale of $36.0 million, of which the Operating Partnership’s share was $8.8 million, which is included in equity in earnings and gains from unconsolidated affiliates in the consolidated financial statements.

Fees from Unconsolidated Affiliates

The Company earned property management, construction, development, legal and leasing fees from its investments in unconsolidated partnerships totaling $1.3 million, $1.2 million, and $0.3 million for the year ended December 31, 2017, 2016, and 2015 respectively, which is included in other revenues in the consolidated financial statements.

In addition, the Company paid to certain unaffiliated partners of its joint ventures, $2.0 million, $2.4 million and $2.5 million during the year ended December 31, 2017, 2016, and 2015 respectively, for leasing commissions, development, management, construction and overhead fees.

Summarized Financial Information of Unconsolidated Affiliates

The following combined and condensed Balance Sheets and Statements of Income, in each period, summarize the financial information of the Company’s investments in unconsolidated affiliates (in thousands):



	December 31,
	2017		2016
Combined and Condensed Balance Sheets
Assets:
Rental property, net	$	518,900	$	576,505
Real estate under development	26,681		18,884
Investment in unconsolidated affiliates	6,853		6,853
Other assets	100,901		75,254
Total assets	$	653,335	$	677,496
Liabilities and partners’ equity:
Mortgage notes payable	$	405,652	$	407,344
Other liabilities	61,932		30,117
Partners’ equity	185,751		240,035
Total liabilities and partners’ equity	$	653,335	$	677,496

Company's share of accumulated equity	$	185,533	$	191,049
Basis differential	95,358		61,827
Deferred fees, net of portion related to the Company's interest	3,472		3,268
Amounts receivable by the Company	2,415		2,193
Investments in and advances to unconsolidated affiliates, net of Company's share of distributions in excess of income from and investments in unconsolidated affiliates	$	286,778	$	258,337



	Year Ended December 31,
	2017			2016			2015
Combined and Condensed Statements of Income
Total revenues	$	83,222		$	84,218		$	43,990
Operating and other expenses	(24,711		)	(25,724		)	(13,721		)
Interest expense	(18,733		)	(16,300		)	(9,178		)
Equity in earnings of unconsolidated affiliates	—			—			66,655
Depreciation and amortization	(24,192		)	(35,432		)	(12,154		)
Loss on debt extinguishment	(154		)	—			—
Gain (loss) on disposition of properties	18,957			(1,340		)	32,623
Net income attributable to unconsolidated affiliates	$	34,389		$	5,422		$	108,215

Company’s share of equity in net income of unconsolidated affiliates	$	26,039		$	40,538		$	37,722
Basis differential amortization	(2,668		)	(1,089		)	(392		)
Company’s equity in earnings of unconsolidated affiliates	$	23,371		$	39,449		$	37,330

Other Assets, Net and Accounts Payable and Other Liabilities

12 Months Ended

Dec. 31, 2017

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Other Assets, net and Accounts Payable and Other Liabilities

Other Assets, Net and Accounts Payable and Other Liabilities

Other assets, net and accounts payable and other liabilities are comprised of the following for the periods presented:



	December 31,
(in thousands)	2017			2016
Other assets, net:
Lease intangibles, net (Note 6)	$	127,571		$	114,584
Deferred charges, net ^(a)	24,589			25,221
Prepaid expenses	16,838			14,351
Other receivables	11,356			9,514
Accrued interest receivable	11,668			9,354
Deposits	6,296			4,412
Due from seller	4,300			4,300
Deferred tax assets	2,096			3,733
Derivative financial instruments (Note 8)	4,402			2,921
Due from related parties	1,479			1,655
Corporate assets	2,369			1,241
Income taxes receivable	1,995			1,500
	$	214,959		$	192,786

(a) Deferred charges, net:
Deferred leasing and other costs	$	41,020		$	40,728
Deferred financing costs	7,786			5,915
	48,806			46,643
Accumulated amortization	(24,217		)	(21,422		)
Deferred charges, net	$	24,589		$	25,221

Accounts payable and other liabilities:
Lease intangibles, net (Note 6)	$	104,478		$	105,028
Accounts payable and accrued expenses	61,420			48,290
Deferred income	31,306			35,267
Tenant security deposits, escrow and other	10,029			14,975
Derivative financial instruments (Note 8)	1,467			3,590
Income taxes payable	176			1,287
Other	1,176			235
	$	210,052		$	208,672

Other Assets, net and Accounts Payable and Other Liabilities

Other Assets, Net and Accounts Payable and Other Liabilities

Other assets, net and accounts payable and other liabilities are comprised of the following for the periods presented:



	December 31,
(in thousands)	2017			2016
Other assets, net:
Lease intangibles, net (Note 6)	$	127,571		$	114,584
Deferred charges, net ^(a)	24,589			25,221
Prepaid expenses	16,838			14,351
Other receivables	11,356			9,514
Accrued interest receivable	11,668			9,354
Deposits	6,296			4,412
Due from seller	4,300			4,300
Deferred tax assets	2,096			3,733
Derivative financial instruments (Note 8)	4,402			2,921
Due from related parties	1,479			1,655
Corporate assets	2,369			1,241
Income taxes receivable	1,995			1,500
	$	214,959		$	192,786

(a) Deferred charges, net:
Deferred leasing and other costs	$	41,020		$	40,728
Deferred financing costs	7,786			5,915
	48,806			46,643
Accumulated amortization	(24,217		)	(21,422		)
Deferred charges, net	$	24,589		$	25,221

Accounts payable and other liabilities:
Lease intangibles, net (Note 6)	$	104,478		$	105,028
Accounts payable and accrued expenses	61,420			48,290
Deferred income	31,306			35,267
Tenant security deposits, escrow and other	10,029			14,975
Derivative financial instruments (Note 8)	1,467			3,590
Income taxes payable	176			1,287
Other	1,176			235
	$	210,052		$	208,672

Lease Intangibles

12 Months Ended

Dec. 31, 2017

Goodwill and Intangible Assets Disclosure [Abstract]

Lease Intangibles

Upon acquisitions of real estate, the Company assesses the fair value of acquired assets (including land, buildings and improvements, and identified intangibles such as above- and below-market leases, including below- market options and acquired in-place leases) and assumed liabilities. The lease intangibles are amortized over the remaining terms of the respective leases, including option periods where applicable.

Intangible assets and liabilities are summarized as follows (in thousands):



	December 31, 2017									December 31, 2016
	Gross Carrying Amount			Accumulated Amortization			Net Carrying Amount			Gross Carrying Amount			Accumulated Amortization			Net Carrying Amount
Amortizable Intangible Assets
In-place lease intangible assets	$	193,821		$	(72,749	)	$	121,072		$	156,420		$	(47,827	)	$	108,593
Above-market rent	16,786			(10,287		)	6,499			16,649			(10,658		)	5,991
	$	210,607		$	(83,036	)	$	127,571		$	173,069		$	(58,485	)	$	114,584

Amortizable Intangible Liabilities
Below-market rent	$	(147,232	)	$	43,391		$	(103,841	)	$	(137,032	)	$	32,004		$	(105,028	)
Above-market ground lease	(671		)	34			(637		)	—			—			—
	$	(147,903	)	$	43,425		$	(104,478	)	$	(137,032	)	$	32,004		$	(105,028	)

During the year ended December 31, 2017, the Company acquired in-place lease intangible assets of $41.6 million, above-market rents of $2.7 million, below-market rents of $10.9 million, and an above-market ground lease of $0.7 million with weighted-average useful lives of 4.1, 4.8, 12.1, and 11.5 years, respectively. Amortization of in-place lease intangible assets is recorded in depreciation and amortization expense and amortization of above-market rent and below-market rent is recorded as a reduction to and increase to rental income, respectively, in the consolidated statements of income. Amortization of above-market ground leases are recorded as a reduction to rent expense in the consolidated statements of income.

The scheduled amortization of acquired lease intangible assets and assumed liabilities as of December 31, 2017 is as follows (in thousands):



Years Ending December 31,	Net Increase in Lease Revenues		Increase to Amortization			Reduction of Rent Expense		Net Income (Expense)
2018	$	10,005	$	(29,005	)	$	58	$	(18,942	)
2019	9,642		(21,678		)	58		(11,978		)
2020	8,655		(16,797		)	58		(8,084		)
2021	7,503		(12,524		)	58		(4,963		)
2022	7,185		(8,778		)	58		(1,535		)
Thereafter	54,352		(32,290		)	347		22,409
Total	$	97,342	$	(121,072	)	$	637	$	(23,093	)

Debt

12 Months Ended

Dec. 31, 2017

Debt Disclosure [Abstract]

Debt

A summary of the Company’s consolidated indebtedness is as follows (dollars in thousands):



	Interest Rate at December 31,		Maturity Date at	Carrying Value at December 31,
	2017	2016	December 31, 2017	2017			2016
Mortgages Payable
Core Fixed Rate	3.88%-5.89%	3.88%-6.65%	February 2024 - April 2035	$	179,870		$	234,875
Core Variable Rate - Swapped^(a)	1.71%-3.77%	1.71%-3.77%	July 2018 - July 2027	74,152			82,250
Total Core Mortgages Payable				254,022			317,125
Fund II Fixed Rate	1.00%-4.75%	1.00%-5.80%	August 2019 - May 2020	205,262			249,762
Fund II Variable Rate	LIBOR+1.39%	LIBOR+0.62%-LIBOR+2.50%	November 2021	—			142,750
Fund II Variable Rate - Swapped^(a)	2.88%	2.88%	November 2021	19,560			19,779
Total Fund II Mortgages Payable				224,822			412,291
Fund III Variable Rate	Prime+0.50% -LIBOR+4.65%	Prime+0.50%-LIBOR+4.65%	May 2018 - December 2021	65,866			83,467
Fund IV Fixed Rate	3.4%-4.50%	3.4%-4.50%	October 2025-June 2026	10,503			10,503
Fund IV Variable Rate	LIBOR+1.70%-LIBOR+3.95%	LIBOR+1.70%-LIBOR+3.95%	January 2018 - April 2022	250,584			233,139
Fund IV Variable Rate - Swapped^(a)	1.78%	1.78%	May 2019 - April 2022	86,851			14,509
Total Fund IV Mortgages Payable				347,938			258,151
Fund V Variable Rate	LIBOR+2.25%	—	October 2020	28,613			—
Net unamortized debt issuance costs				(12,943		)	(16,642		)
Unamortized premium				856			1,336
Total Mortgages Payable				$	909,174		$	1,055,728
Unsecured Notes Payable
Core Unsecured Term Loans	LIBOR+1.30%-LIBOR+1.60%	LIBOR+1.30%-LIBOR+1.60%	July 2020 - December 2022	$	—		$	51,194
Core Variable Rate Unsecured Term Loans - Swapped^(a)	1.24%-3.77%	1.24%-3.77%	July 2018 - March 2025	300,000			248,806
Total Core Unsecured Notes Payable				300,000			300,000
Fund II Unsecured Notes Payable	LIBOR+1.40%	—	September 2020	31,500			—
Fund IV Term Loan/Subscription Facility	LIBOR+1.65%-LIBOR+2.75%	LIBOR+1.65%-LIBOR+2.75%	December 2018 - October 2019	40,825			134,636
Fund V Subscription Facility	LIBOR+1.60%	—	May 2020	103,300			—
Net unamortized debt issuance costs				(1,890		)	(1,646		)
Total Unsecured Notes Payable				$	473,735		$	432,990
Unsecured Line of Credit
Core Unsecured Line of Credit	LIBOR+1.40%	LIBOR+1.40%	June 2020	$	18,048		$	—
Core Unsecured Line of Credit - Swapped^(a)	1.24%-3.77%	—	July 2018 - March 2025	23,452			—
Total Unsecured Line of Credit				$	41,500		$	—

Total Debt - Fixed Rate ^(b)				$	899,650		$	860,486
Total Debt - Variable Rate ^(c)				538,736			645,185
Total Debt				1,438,386			1,505,671
Net unamortized debt issuance costs				(14,833		)	(18,289		)
Unamortized premium				856			1,336
Total Indebtedness				$	1,424,409		$	1,488,718

__________


(a)	At December 31, 2017, the stated rates ranged from LIBOR + 1.65% to LIBOR +1.90% for Core variable-rate debt; LIBOR + 1.39% for Fund II variable-rate debt; PRIME + 0.50% to LIBOR +4.65% for Fund III variable-rate debt; LIBOR + 1.70% to LIBOR +3.95% for Fund IV variable-rate debt, LIBOR + 2.25% for Fund V and LIBOR + 1.30% to LIBOR +1.60% for Core variable-rate unsecured notes.


(b)	Includes $504,018 and $365,343, respectively, of variable-rate debt that has been fixed with interest rate swap agreements as of the periods presented.


(c)	Includes $141.1 million and $186.6 million, respectively, of variable-rate debt that is subject to interest cap agreements.

Mortgages Payable

During the year ended December 31, 2017, the Company obtained eleven new non-recourse mortgages totaling $162.9 million with a weighted-average interest rate of LIBOR + 3.47% collateralized by eleven properties, which mature between February 14, 2020 and December 1, 2022. The Company entered into interest rate swap contracts to effectively fix the variable portion of the interest rates of eight of these obligations with a notional value of $73.3 million at a weighted-average rate of 2.11%. During 2017, the Company repaid thirteen mortgages in full, which had a total balance of $280.8 million and a weighted-average interest rate of 3.90%, and made scheduled principal payments of $1.0 million. At December 31, 2017 and December 31, 2016, the Company’s mortgages were collateralized by 42 and 39 properties, respectively, and the related tenant leases. Certain loans are cross-collateralized and contain cross-default provisions. The loan agreements contain customary representations, covenants and events of default. Certain loan agreements require the Company to comply with affirmative and negative covenants, including the maintenance of debt service coverage and leverage ratios. A portion of the Company’s variable-rate mortgage debt has been effectively fixed through certain cash flow hedge transactions (Note 8).

The mortgage loan related to Brandywine Holdings in the Company’s Core Portfolio amounted to $26.3 million and was in default at December 31, 2017 and December 31, 2016. This loan bears interest at 5.99%, excluding default interest of 5%, and is collateralized by a property, in which the Company holds a 22% controlling interest. During the year ended December 31, 2015, the Company recognized an impairment charge on this property (Note 8). In April 2017, the lender on this mortgage initiated a lawsuit against the Company for the full balance of the principal, accrued interest as well as penalties and fees aggregating approximately $32.1 million. The Company’s management believes that the mortgage is not recourse to the Company and that the suit is without merit.

See Note 17 for information about additional financing obtained after December 31, 2017.

Unsecured Notes Payable

Unsecured notes payable for which total availability was $70.3 million and $9.9 million at December 31, 2017 and December 31, 2016, respectively, are comprised of the following:


•	In the Core portfolio there are outstanding at both December 31, 2017 and December 31, 2016 $300.0 million of unsecured term loans including a $150.0 million term loan and three $50.0 million term loans. All of the Core term loans are swapped to fixed rates. The Core unsecured term loans were refinanced in February 2018 (Note 17).

•

During 2017, Fund II obtained a $40.0 million term loan secured by the real estate assets of City Point Phase II with an interest rate of LIBOR plus 140 basis points and maturing in September 2020. The Fund II loan is also guaranteed by the Company and the Operating Partnership. The outstanding balance and total available credit of the Fund II term loan was $31.5 million and $8.5 million, respectively, at December 31, 2017.

•

At Fund IV there are a $41.8 million bridge facility and a $21.5 million subscription line. The outstanding balance of the Fund IV bridge facility was $40.8 million and $40.1 million at December 31, 2017 and December 31, 2016, respectively. Total availability was $1.0 million and $0 at December 31, 2017 and December 31, 2016. The outstanding balance of the Fund IV subscription line was $0.0 million and $94.5 million and total available credit was $14.1 million and $5.5 million at December 31, 2017 and December 31, 2016, reflecting letters of credit of $7.4 million and $0, respectively.

•

During 2017, Fund V obtained a $150.0 million subscription line collateralized by Fund V’s unfunded capital commitments with an interest rate of LIBOR plus 160 basis points and maturing in May 2020. The Fund V subscription line is also guaranteed by the Operating Partnership. The outstanding balance and total available credit of the Fund V subscription line was $103.3 million and $46.7 million, respectively, at December 31, 2017.

Unsecured Line of Credit

The Company had a total of $96.2 million and $138.7 million available under its $150.0 million Core unsecured revolving line of credit reflecting borrowings of $41.5 million and $0 and letters of credit of $12.3 million and $11.3 million at December 31, 2017 and December 31, 2016, respectively. At December 31, 2017 a portion of the Core unsecured revolving line of credit was swapped to a fixed rate. The Core unsecured revolving line of credit was refinanced in February 2018 (Note 17).

Scheduled Debt Principal Payments

The scheduled principal repayments of the Company’s consolidated indebtedness, as of December 31, 2017 are as follows (in thousands):



Year Ending December 31,
2018	$	94,400
2019	213,573
2020	576,379
2021	255,027
2022	98,840
Thereafter	200,167
	1,438,386
Unamortized fair market value of assumed debt	856
Net unamortized debt issuance costs	(14,833		)
Total indebtedness	$	1,424,409

See Note 4 for information about liabilities of the Company’s unconsolidated affiliates.

Financial Instruments and Fair Value Measurements

12 Months Ended

Dec. 31, 2017

Fair Value Disclosures [Abstract]

Financial Instruments and Fair Value Measurements

The fair value of an asset is defined as the exit price, which is the amount that would either be received when an asset is sold or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The guidance establishes a three-tier fair value hierarchy based on the inputs used in measuring fair value. These tiers are: Level 1, for which quoted market prices for identical instruments are available in active markets, such as money market funds, equity securities, and U.S. Treasury securities; Level 2, for which there are inputs other than quoted prices included within Level 1 that are observable for the instrument, such as certain derivative instruments including interest rate caps and interest rate swaps; and Level 3, for financial instruments or other assets/liabilities that do not fall into Level 1 or Level 2 and for which little or no market data exists, therefore requiring the Company to develop its own assumptions.

Items Measured at Fair Value on a Recurring Basis

The methods and assumptions described below were used to estimate the fair value of each class of financial instrument. For significant Level 3 items, the Company has also provided the unobservable inputs along with their weighted-average ranges.

Money Market Funds — The Company has money market funds, which are included in Cash and cash equivalents in the consolidated financial statements, are comprised of government securities and/or U.S. Treasury bills. These funds were classified as Level 1 as we used quoted prices from active markets to determine their fair values.

Derivative Assets — The Company has derivative assets, which are included in Other assets, net in the consolidated financial statements, are comprised of interest rate swaps and caps. The derivative instruments were measured at fair value using readily observable market inputs, such as quotations on interest rates, and were classified as Level 2 as these instruments are custom, over-the-counter contracts with various bank counterparties that are not traded in an active market. See “Derivative Financial Instruments,” below.

Derivative Liabilities — The Company has derivative liabilities, which are included in Accounts payable and other liabilities in the consolidated financial statements, are comprised of interest rate swaps and caps. These derivative instruments were measured at fair value using readily observable market inputs, such as quotations on interest rates, and were classified as Level 2 because they are custom, over-the-counter contracts with various bank counterparties that are not traded in an active market. See “Derivative Financial Instruments,” below.

The Company did not have any transfers into or out of Level 1, Level 2, and Level 3 measurements during the years ended December 31, 2017, 2016 or 2015.

The following table presents the Company’s fair value hierarchy for those assets and liabilities measured at fair value on a recurring basis (in thousands):



	December 31, 2017						December 31, 2016
	Level 1		Level 2		Level 3		Level 1		Level 2		Level 3
Assets
Money Market Funds	$	3	$	—	$	—	$	20,001	$	—	$	—
Derivative financial instruments	—		4,402		—		—		2,921		—
Liabilities
Derivative financial instruments	—		1,467		—		—		3,590		—

In instances where the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level input that is significant to the fair value measurement in its entirety. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the asset or liability.

Items Measured at Fair Value on a Nonrecurring Basis (Including Impairment Charges)

During the year ended December 31, 2017, the Company recognized an impairment charge of $3.8 million, inclusive of an amount attributable to a noncontrolling interest of $2.7 million, on Fund II’s City Point Condominium Tower I property, which was classified as held for sale at September 30, 2017, in order to reduce the carrying value of the property to its estimated fair value. In addition, the Company recognized an impairment charge of $10.6 million, inclusive of an amount attributable to a noncontrolling interest of $7.6 million, on a property classified as held for sale at December 31, 2017 (Note 2), in order to reduce the carrying value of the property to its estimated fair value. These fair value measurements approximated the estimated selling prices less estimated costs to sell.

The Company did not record any impairment charges during the year ended December 31, 2016. During the year ended December 31, 2015, as a result of the loss of a key anchor tenant at a property located in Wilmington, Delaware, the Company recorded an impairment charge of $5.0 million on its Brandywine Holdings property, which is included in the consolidated statement of income for the year ended December 31, 2015. The Operating Partnership's share of this charge, net of the noncontrolling interest, was $1.1 million. The property is collateral for $26.3 million of non-recourse mortgage debt which matured July 1, 2016 and is currently in default (Note 7).

Derivative Financial Instruments

The Company had the following interest rate swaps for the periods presented (dollars in thousands):



	Aggregate Notional Amount				Strike Rate			Balance Sheet Location	Fair Value
Derivative Instrument	Aggregate Notional Amount		Effective Date	Maturity Date	Low		High	Balance Sheet Location	December 31, 2017			December 31, 2016
Core
Interest Rate Swaps	$	149,036	Oct 2011 - March 2015	July 2018 - Mar 2025	1.38%	—	3.77%	Other Liabilities	$	(1,438	)	$	(3,218	)
Interest Rate Swaps	248,571		Sep 2012 - July 2017	July 2020 - July 2027	1.24%	—	3.77%	Other Assets	4,076			2,609
	$	397,607							$	2,638		$	(609	)

Fund II
Interest Rate Swap	$	19,560	October 2014	November 2021	2.88%	—	2.88%	Other Liabilities	$	(29	)	$	(228	)
Interest Rate Cap	29,500		April 2013	April 2018	4.00%	—	4.00%	Other Assets	—			—
	$	49,060							$	(29	)	$	(228	)

Fund III
Interest Rate Cap	$	58,000	Dec 2016	Jan 2020	3.00%	—	3.00%	Other Assets	$	14		$	127

Fund IV
Interest Rate Swaps	$	86,851	May 2014 - March 2017	May 2019 - April 2022	1.78%	—	2.11%	Other Assets	$	295		$	—
Interest Rate Swaps	—		May 2014 - March 2017	May 2019 - April 2022	1.78%	—	2.11%	Other Liabilities	—			$	(144	)
Interest Rate Caps	108,900		July 2016 - November 2016	August 2019 - December 2019	3.00%	—	3.00%	Other Assets	17			185
	$	195,751							$	312		$	41

Total asset derivatives									$	4,402		$	2,921
Total liability derivatives									$	(1,467	)	$	(3,590	)

All of the Company’s derivative instruments have been designated as cash flow hedges and hedge the future cash outflows on variable-rate debt (Note 7). It is estimated that approximately $0.6 million included in accumulated other comprehensive (loss) income related to derivatives will be reclassified to interest expense in the 2018 results of operation. As of December 31, 2017 and 2016, no derivatives were designated as fair value hedges or hedges of net investments in foreign operations. Additionally, the Company does not use derivatives for trading or speculative purposes and currently does not have any derivatives that are not designated hedges.

Risk Management Objective of Using Derivatives

The Company is exposed to certain risks arising from both its business operations and economic conditions. The Company manages economic risks, including interest rate, liquidity and credit risk, primarily by managing the amount, sources and duration of its debt funding and, from time to time, through the use of derivative financial instruments. The Company enters into derivative financial instruments to manage exposures that result in the receipt or payment of future known and uncertain cash amounts, the values of which are determined by interest rates. The Company’s derivative financial instruments are used to manage differences in the amount, timing and duration of the Company’s known or expected cash receipts and its known or expected cash payments principally related to the Company’s investments and borrowings.

The Company is exposed to credit risk in the event of non-performance by the counterparties to the Swaps if the derivative position has a positive balance. The Company believes it mitigates its credit risk by entering into Swaps with major financial institutions. The Company continually monitors and actively manages interest costs on its variable-rate debt portfolio and may enter into additional interest rate swap positions or other derivative interest rate instruments based on market conditions. The Company has not entered, and does not plan to enter, into any derivative financial instruments for trading or speculative purposes.

The following table presents the location in the financial statements of the income (losses) recognized related to the Company’s cash flow hedges (in thousands):



	Year Ended December 31,
	2017		2016			2015
Amount of (loss) income related to the effective portion recognized in other comprehensive income	$	634	$	(646	)	$	(5,061	)
Amount of loss related to the effective portion subsequently reclassified to earnings	—		—			—
Amount of gain (loss) related to the ineffective portion and amount excluded from effectiveness testing	—		—			—

Credit Risk-Related Contingent Features

The Company has agreements with each of its Swap counterparties that contain a provision whereby if the Company defaults on certain of its unsecured indebtedness the Company could also be declared in default on its swaps, resulting in an acceleration of payment under the swaps.

Other Financial Instruments

The Company’s other financial instruments had the following carrying values and fair values as of the dates shown (dollars in thousands):



		December 31, 2017				December 31, 2016
	Level	Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
Notes Receivable^(a)	3	$	153,829	$	151,712	$	276,163	$	272,052
Mortgage and Other Notes Payable, net^(a)	3	909,174		921,891		1,055,728		1,077,926
Investment in non-traded equity securities ^(b)	3	411		22,824		802		25,194
Unsecured notes payable and Unsecured line of credit, net^(c)	2	515,235		515,330		434,636		435,779

__________

(a)

The Company determined the estimated fair value of these financial instruments using a discounted cash flow model with rates that take into account the credit of the borrower or tenant, where applicable, and interest rate risk. The Company also considered the value of the underlying collateral, taking into account the quality of the collateral, the credit quality of the borrower, the time until maturity and the current market interest rate environment.


(b)	Represents Fund II’s cost-method investment in Albertson’s supermarkets (Note 4).

(c)

The Company determined the estimated fair value of the unsecured notes payable and unsecured line of credit using quoted market prices in an open market with limited trading volume where available. In cases where there was no trading volume, the Company determined the estimated fair value using a discounted cash flow model using a rate that reflects the average yield of similar market participants.

The Company’s cash and cash equivalents, restricted cash, accounts receivable, accounts payable and certain financial instruments included in other assets and other liabilities had fair values that approximated their carrying values at December 31, 2017.

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The Company is involved in various matters of litigation arising in the normal course of business. While the Company is unable to predict with certainty the amounts involved, the Company’s management and counsel are of the opinion that, when such litigation is resolved, the Company’s resulting liability, if any, will not have a significant effect on the Company’s consolidated financial position, results of operations, or liquidity. The Company's policy is to accrue legal expenses as they are incurred. Commitments and Guaranties In conjunction with the development and expansion of various properties, the Company has entered into agreements with general contractors for the construction or development of properties aggregating approximately $92.2 million and $85.4 million as of December 31, 2017 and December 31, 2016, respectively. At each of December 31, 2017 and December 31, 2016, the Company had letters of credit outstanding of $19.7 million and $11.3 million, respectively. The Company has not recorded any obligation associated with these letters of credit. The majority of the letters of credit are collateral for existing indebtedness and other obligations of the Company.

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income

12 Months Ended

Dec. 31, 2017

Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income

Shareholders’ Equity, Noncontrolling Interests and Other Comprehensive Income

Common Shares

The Company completed the following transactions in its common shares during the year ended December 31, 2017:


•	The Company withheld 4,314 Restricted Shares to pay the employees’ statutory minimum income taxes due on the value of the portion of their Restricted Shares that vested.


•	The Company recognized Common Share and Common OP Unit-based compensation totaling $8.4 million in connection with Restricted Shares and Units (Note 13).


•	At the May 10 Shareholder Meeting, Shareholders approved an amendment to the Company’s Declaration of Trust to increase the authorized share capital of the Company from 100 million shares of beneficial interest to 200 million shares which became effective on July 24, 2017.

The Company completed the following transactions in its common shares during the year ended December 31, 2016:

•

The Company issued 4,500,000 Common Shares under its at-the-market (“ATM”) equity programs, generating gross proceeds of $157.6 million and net proceeds of $155.7 million. The Company has established a new ATM equity program, effective July 2016, with an additional aggregate offering amount of up to $250.0 million of gross proceeds from the sale of Common Shares, replacing its $200.0 million program that was launched in 2014. As of December 31, 2016 and December 31, 2017, there was $218.0 million remaining under this $250.0 million program.


•	The Company entered into a forward sale agreement to issue 3,600,000 Common Shares for gross proceeds of $126.8 million and net proceeds of $124.5 million. As of December 31, 2016, these shares have been physically settled.


•	The Company issued 4,830,000 Common Shares in a public offering, generating gross proceeds of $175.2 million and net proceeds of $172.1 million.


•	The Company withheld 3,152 Restricted Shares to pay the employees’ statutory minimum income taxes due on the value of the portion of their Restricted Shares that vested.


•	The Company recognized accrued Common Share and Common OP Unit-based compensation totaling $10.9 million in connection with the vesting of Restricted Shares and Units (Note 13).

Share Repurchases

The Company has a share repurchase program that authorizes management, at its discretion, to repurchase up to $20.0 million of its outstanding Common Shares. The program may be discontinued or extended at any time. There were no Common Shares repurchased by the Company during the year ended December 31, 2017 or the year ended December 31, 2016. Under this program the Company has repurchased 2.1 million Common Shares, none of which were repurchased after December 2001. As of December 31, 2017, management may repurchase up to approximately $7.5 million of the Company’s outstanding Common Shares under this program. During 2018, the Company revised its share repurchase program (Note 17).

Dividends and Distributions

On November 8, 2017, the Board of Trustees declared an increase of $0.01 to the $0.27 per Common Share regular quarterly cash dividend, which was paid on January 13, 2018 to holders of record as of December 29, 2017.

On November 8, 2016, the Board of Trustees declared an increase of $0.01 to the regular quarterly cash dividend of $0.25 to $0.26 per Common Share, which was paid on January 13, 2017 to holders of record as of December 30, 2016. In addition, on November 8, 2016, the Board of Trustees declared a special cash dividend of $0.15 per Common Share with the same record and payment date as the regular quarterly dividend. The special dividend is a result of the taxable capital gains for 2016 arising from property dispositions within the Funds.

Accumulated Other Comprehensive Income

The following table sets forth the activity in accumulated other comprehensive (loss) income for the year ended December 31, 2017 and 2016 (in thousands):



	Gains or Losses on Derivative Instruments
Balance at January 1, 2017	$	(798	)

Other comprehensive loss before reclassifications	634
Reclassification of realized interest on swap agreements	3,317
Net current period other comprehensive loss	3,951
Net current period other comprehensive loss attributable to noncontrolling interests	(539		)
Balance at December 31, 2017	$	2,614

Balance at January 1, 2016	$	(4,463	)

Other comprehensive loss before reclassifications	(646		)
Reclassification of realized interest on swap agreements	4,576
Net current period other comprehensive loss	3,930
Net current period other comprehensive loss attributable to noncontrolling interests	(265		)
Balance at December 31, 2016	$	(798	)

Noncontrolling Interests

The following table summarizes the change in the noncontrolling interests for the year ended December 31, 2017 and 2016 (dollars in thousands):



	Noncontrolling Interests in Operating Partnership ^(a)			Noncontrolling Interests in Partially-Owned Affiliates ^(b)			Total

Balance at January 1, 2017	$	95,422		$	494,126		$	589,548
Distributions declared of $1.05 per Common OP Unit	(6,453		)	—			(6,453		)
Net income (loss) for the period January 1 through December 31, 2017	4,159			(1,321		)	2,838
Conversion of 5,000 Preferred and 81,453 Common OP Units to Common Shares by limited partners of the Operating Partnership	(1,541		)	—			(1,541		)
Other comprehensive income - unrealized loss on valuation of swap agreements	85			(232		)	(147		)
Reclassification of realized interest expense on swap agreements	141			545			686
Noncontrolling interest contributions	—			85,206			85,206
Noncontrolling interest distributions	—			(32,805		)	(32,805		)
Employee Long-term Incentive Plan Unit Awards	10,457			—			10,457
Rebalancing adjustment ^(d)	651			—			651
Balance at December 31, 2017	$	102,921		$	545,519		$	648,440

Balance at January 1, 2016	$	96,340		$	324,526		$	420,866
Distributions declared of $1.16 per Common OP Unit	(6,753		)	—			(6,753		)
Net income for the period January 1 through December 31, 2016	5,002			56,814			61,816
Conversion of 351,250 Common OP Units to Common Shares by limited partners of the Operating Partnership	(7,892		)	—			(7,892		)
Issuance of Common and Preferred OP Units to acquire real estate	31,429			—			31,429
Acquisition of noncontrolling interests ^(c)	—			(25,925		)	(25,925		)
Other comprehensive income - unrealized loss on valuation of swap agreements	(43		)	(289		)	(332		)
Change in control of previously unconsolidated investment	—			(75,713		)	(75,713		)
Reclassification of realized interest expense on swap agreements	223			374			597
Noncontrolling interest contributions	—			295,108			295,108
Noncontrolling interest distributions	—			(80,769		)	(80,769		)
Employee Long-term Incentive Plan Unit Awards	12,768			—			12,768
Rebalancing adjustment ^(d)	(35,652		)	—			(35,652		)
Balance at December 31, 2016	$	95,422		$	494,126		$	589,548

__________

(a)

Noncontrolling interests in the Operating Partnership are comprised of (i) the limited partners’ 3,328,873 and 3,308,875 Common OP Units at December 31, 2017 and 2016, respectively; (ii) 188 Series A Preferred OP Units at December 31, 2017 and 2016; (iii) 136,593 and 141,593 Series C Preferred OP Units at December 31, 2017 and 2016, respectively; and (iv) 2,274,147 and 1,997,099 LTIP units as of December 31, 2017 and 2016, respectively, as discussed in Share Incentive Plan (Note 13). Distributions declared for Preferred OP Units are reflected in net income in the table above.


(b)	Noncontrolling interests in partially-owned affiliates comprise third-party interests in Funds II, III, IV and V, and Mervyns I and II, and six other subsidiaries.


(c)	During the first quarter of 2016, the Company acquired an additional 8.3% interest in Fund II from a limited partner for $18.4 million, giving the Company an aggregate 28.33% interest. Amount in the table above represents the book value of this transaction.


(d)	Adjustment reflects the difference between the fair value of the consideration received or paid and the book value of the Common Shares, Common OP Units, Preferred OP Units, and LTIP Units involving changes in ownership (the “Rebalancing”).

Preferred OP Units

There were no issuances of Preferred OP Units and 5,000 Series C Preferred OP Units were exchanged for common shares of the Company during the year ended December 31, 2017.

In 1999 the Operating Partnership issued 1,580 Series A Preferred OP Units in connection with the acquisition of a property, which have a stated value of $1,000 per unit, and are entitled to a preferred quarterly distribution of the greater of (i) $22.50 (9% annually) per Series A Preferred OP Unit or (ii) the quarterly distribution attributable to a Series A Preferred OP Unit if such unit was converted into a Common OP Unit. Through December 31, 2016, 1,392 Series A Preferred OP Units were converted into 185,600 Common OP Units and then into Common Shares. The 188 remaining Series A Preferred OP Units are currently convertible into Common OP Units based on the stated value divided by $7.50. Either the Company or the holders can currently call for the conversion of the Series A Preferred OP Units at the lesser of $7.50 or the market price of the Common Shares as of the conversion date.

During the first quarter of 2016, the Operating Partnership issued 442,478 Common OP Units and 141,593 Series C Preferred OP Units to a third party to acquire Gotham Plaza (Note 4). The Series C Preferred OP Units have a value of $100.00 per unit and are entitled to a preferred quarterly distribution of $0.9375 per unit and are convertible into Common OP Units at a rate based on the share price at the time of conversion. If the share price is below $28.80 on the conversion date, each Series C Preferred OP Unit will be convertible into 3.4722 Common OP Units. If the share price is between $28.80 and $35.20 on the conversion date, each Series C Preferred OP Unit will be convertible into a number of Common OP Units equal to $100.00 divided by the closing share price. If the share price is above $35.20 on the conversion date, each Series C Preferred OP Unit will be convertible into 2.8409 Common OP Units. The Series C Preferred OP Units have a mandatory conversion date of December 31, 2025, at which time all units that have not been converted will automatically be converted into Common OP Units based on the same calculations.

Leases

12 Months Ended

Dec. 31, 2017

Leases [Abstract]

Leases

Operating Leases

The Company is engaged in the operation of shopping centers and other retail properties that are either owned or, with respect to certain shopping centers, operated under long-term ground leases that expire at various dates through June 20, 2066, with renewal options. Space in the shopping centers is leased to tenants pursuant to agreements that provide for terms ranging generally from one month to ninety-nine years and generally provide for additional rents based on certain operating expenses as well as tenants’ sales volumes.

The Company leases land at seven of its shopping centers, which are accounted for as operating leases and generally provide the Company with renewal options. Ground rent expense was $1.4 million, $1.2 million and $1.7 million (including capitalized ground rent at a property under development of $0.1 million, $0.6 million and $0.9 million) for the years ended December 31, 2017, 2016 and 2015, respectively. The leases terminate at various dates between 2020 and 2066. These leases provide the Company with options to renew for additional terms aggregating from 25 to 71 years. The Company also leases space for its corporate office. Office rent expense under this lease was $1.0 million, $1.0 million and $1.4 million for the years ended December 31, 2017, 2016 and 2015, respectively.

Capital Lease

During 2016, the Company entered into a 49-year master lease at 991 Madison Avenue, which is accounted for as a capital lease. During the years ended December 31, 2017 and 2016, payments for this lease totaled $2.5 million and $1.3 million respectively. The lease was initially valued at $76.6 million, which represents the total discounted payments to be made under the lease. The property under the capital lease is included in Note 2.

Lease Obligations

The scheduled future minimum (i) rental revenues from rental properties under the terms of all non-cancelable tenant leases, assuming no new or renegotiated leases or option extensions for such premises and (ii) rental payments under the terms of all non-cancelable operating and capital leases in which the Company is the lessee, principally for office space and ground leases, as of December 31, 2017, are summarized as follows (in thousands):



Year Ending December 31,	Minimum Rental Revenues		Minimum Rental Payments
2018	$	165,893	$	4,540
2019	163,576		4,560
2020	149,453		4,356
2021	130,834		4,302
2022	111,958		4,395
Thereafter	514,271		185,014
Total	$	1,235,985	$	207,167

A ground lease expiring during 2078 provides the Company with an option to purchase the underlying land during 2031. If the Company does not exercise the option, the rents that will be due are based on future values and as such are not determinable at this time. Accordingly, the above table does not include rents for this lease beyond 2031.

During the years ended December 31, 2017, 2016 and 2015, no single tenant collectively comprised more than 10% of the Company’s consolidated total revenues.

Segment Reporting

12 Months Ended

Dec. 31, 2017

Segment Reporting [Abstract]

Segment Reporting

The Company has three reportable segments: Core Portfolio, Funds and Structured Financing. The Company’s Core Portfolio consists primarily of high-quality retail properties located primarily in high-barrier-to-entry, densely-populated metropolitan areas with a long-term investment horizon. The Company’s Funds hold primarily retail real estate in which the Company co-invests with high-quality institutional investors. The Company’s Structured Financing segment consists of earnings and expenses related to notes and mortgages receivable which are held within the Core Portfolio or the Funds (Note 3). Fees earned by the Company as the general partner or managing member of the Funds are eliminated in the Company’s consolidated financial statements and are not presented in the Company’s segments.

The following tables set forth certain segment information for the Company (in thousands):



	As of or for the Year Ended December 31, 2017
	Core Portfolio			Funds			Structured Financing		Unallocated			Total
Revenues	$	169,975		$	80,287		$	—	$	—		$	250,262
Depreciation and amortization	(61,705		)	(43,229		)	—		—			(104,934		)
Property operating expenses, other operating and real estate taxes	(45,349		)	(34,449		)	—		—			(79,798		)
Impairment charges	—			(14,455		)	—		—			(14,455		)
General and administrative expenses	—			—			—		(33,756		)	(33,756		)
Operating income	62,921			(11,846		)	—		(33,756		)	17,319
Gain on disposition of properties	—			48,886			—		—			48,886
Interest income	—			—			29,143		—			29,143
Equity in earnings of unconsolidated affiliates inclusive of gains on disposition of properties	3,735			19,636			—		—			23,371
Interest expense	(28,618		)	(30,360		)	—		—			(58,978		)
Gain on change in control	5,571			—			—		—			5,571
Income tax provision	—			—			—		(1,004		)	(1,004		)
Net income	43,609			26,316			29,143		(34,760		)	64,308
Net income attributable to noncontrolling interests	(1,107		)	(1,731		)	—		—			(2,838		)
Net income attributable to Acadia	$	42,502		$	24,585		$	29,143	$	(34,760	)	$	61,470

Real estate at cost	$	2,032,485		$	1,433,997		$	—	$	—		$	3,466,482
Total assets	$	2,305,663		$	1,500,755		$	153,829	$	—		$	3,960,247
Cash paid for acquisition of real estate	$	—		$	200,429		$	—	$	—		$	200,429
Cash paid for development and property improvement costs	$	49,339		$	66,116		$	—	$	—		$	115,455



	As of or for the Year Ended December 31, 2016
	Core Portfolio			Funds			Structured Financing		Unallocated			Total
Revenues	$	150,211		$	39,728		$	—	$	—		$	189,939
Depreciation and amortization	(54,582		)	(15,429		)	—		—			(70,011		)
Property operating expenses, other operating and real estate taxes	(39,598		)	(17,793		)	—		—			(57,391		)
General and administrative expenses	—			—			—		(40,648		)	(40,648		)
Operating income	56,031			6,506			—		(40,648		)	21,889
Gain on disposition of properties	—			81,965			—		—			81,965
Interest income	—			—			25,829		—			25,829
Equity in earnings of unconsolidated affiliates inclusive of gains on disposition of properties	3,774			35,675			—		—			39,449
Interest expense	(27,435		)	(7,210		)	—		—			(34,645		)
Income tax benefit	—			—			—		105			105
Net income	32,370			116,936			25,829		(40,543		)	134,592
Net income attributable to noncontrolling interests	(3,411		)	(58,405		)	—		—			(61,816		)
Net income attributable to Acadia	$	28,959		$	58,531		$	25,829	$	(40,543	)	$	72,776

Real estate at cost	$	1,982,763		$	1,399,237		$	—	$	—		$	3,382,000
Total assets	$	2,271,620		$	1,448,177		$	276,163	$	—		$	3,995,960
Cash paid for acquisition of real estate	$	323,880		$	171,764		$	—	$	—		$	495,644
Cash paid for development and property improvement costs	$	13,434		$	136,000		$	—	$	—		$	149,434



	As of or for the Year Ended December 31, 2015
	Core Portfolio			Funds			Structured Financing		Unallocated			Total
Revenues	$	150,015		$	49,048		$	—	$	—		$	199,063
Depreciation and amortization	(46,223		)	(14,528		)	—		—			(60,751		)
Property operating expenses, other operating and real estate taxes	(37,259		)	(21,223		)	—		—			(58,482		)
Impairment charges	(5,000		)	—			—		—			(5,000		)
General and administrative expenses	—			—			—		(30,368		)	(30,368		)
Operating income	61,533			13,297			—		(30,368		)	44,462
Gain on disposition of properties	—			89,063			—		—			89,063
Interest income	—			—			16,603		—			16,603
Equity in earnings of unconsolidated affiliates inclusive of gains on disposition of properties	1,169			36,161			—		—			37,330
Other	—			—			1,596		—			1,596
Interest expense	(27,945		)	(9,352		)	—		—			(37,297		)
Income tax provision	—			—			—		(1,787		)	(1,787		)
Net income	34,757			129,169			18,199		(32,155		)	149,970
Net income attributable to noncontrolling interests	(140		)	(84,122		)	—		—			(84,262		)
Net income attributable to Acadia	$	34,617		$	45,047		$	18,199	$	(32,155	)	$	65,708

Real estate at cost	$	1,572,681		$	1,163,602		$	—	$	—		$	2,736,283
Total assets	$	1,662,092		$	1,223,039		$	147,188	$	—		$	3,032,319
Cash paid for acquisition of real estate	$	181,884		$	156,816		$	—	$	—		$	338,700
Cash paid for development and property improvement costs	$	16,505		$	147,810		$	—	$	—		$	164,315

Share Incentive and Other Compensation

12 Months Ended

Dec. 31, 2017

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Share Incentive and Other Compensation

Share Incentive Plan

The Second Amended and Restated 2006 Incentive Plan (the “Share Incentive Plan”) authorizes the Company to issue options, Restricted Shares, LTIP Units and other securities (collectively “Awards”) to, among others, the Company’s officers, trustees and employees. At December 31, 2017 a total of 1,756,317 shares remained available to be issued under the Share Incentive Plan.

Restricted Shares and LTIP Units

During the year ended December 31, 2017, the Company issued 306,635 LTIP Units and 7,628 Restricted Share Units to employees of the Company pursuant to the Share Incentive Plan. These awards were measured at their fair value on the grant date, which was established as the market price of the Company’s Common Shares as of the close of trading on the day preceding the grant date. The total value of the above Restricted Share Units and LTIP Units as of the grant date was $9.5 million, of which $2.2 million was recognized as compensation expense in 2016, and $7.3 million will be recognized as compensation expense over the remaining vesting period. Total long-term incentive compensation expense, including the expense related to the Share Incentive Plan, was $8.4 million and $10.9 million for the year ended December 31, 2017 and 2016, respectively and is recorded in General and Administrative on the Consolidated Statements of Income.

In addition, members of the Board of Trustees (the “Board”) have been issued shares and units under the Share Incentive Plan. During 2017, the Company issued 11,814 Restricted Shares and 11,105 LTIP Units to Trustees of the Company in connection with Trustee fees. Vesting with respect to 3,864 of the Restricted Shares and 5,805 of the LTIP Units will be on the first anniversary of the date of issuance and 7,950 of the Restricted Shares and 5,300 of the LTIP Units vest over three years with 33% vesting on each of the next three anniversaries of the issuance date. The Restricted Shares do not carry voting rights or other rights of Common Shares until vesting and may not be transferred, assigned or pledged until the recipients have a vested non-forfeitable right to such shares. Dividends are not paid currently on unvested Restricted Shares, but are paid cumulatively from the issuance date through the applicable vesting date of such Restricted Shares. Total trustee fee expense, including the expense related to the Share Incentive Plan, was $1.2 million and $1.1 million for the year ended December 31, 2017 and 2016, respectively.

In 2009, the Company adopted the Long Term Investment Alignment Program (the “Program”) pursuant to which the Company may grant awards to employees, entitling them to receive up to 25% of any potential future payments of Promote to the Operating Partnership from Funds III and IV. The Company has granted such awards to employees representing 25% of the potential Promote payments from Fund III to the Operating Partnership and 14.4% of the potential Promote payments from Fund IV to the Operating Partnership. Payments to senior executives under the Program require further Board approval at the time any potential payments are due pursuant to these grants. Compensation relating to these awards will be recognized in each reporting period in which Board approval is granted.

As payments to other employees are not subject to further Board approval, compensation relating to these awards will be recorded based on the estimated fair value at each reporting period in accordance with ASC Topic 718, Compensation– Stock Compensation. The awards in connection with Fund IV were determined to have no intrinsic value as of December 31, 2017.

Compensation expense of $0.6 million and $5 million was recognized for the year ended December 31, 2017 and 2016, respectively, related to the Program in connection with Fund III.

A summary of the status of the Company’s unvested Restricted Shares and LTIP Units is presented below:



Unvested Restricted Shares and LTIP Units	Common Restricted Shares		Weighted Grant-Date Fair Value		LTIP Units		Weighted Grant-Date Fair Value
Unvested at January 1, 2016	49,899		$	25.90	1,020,121		$	23.92
Granted	21,675		33.35		359,484		34.40
Vested	(24,886	)	29.17		(522,680	)	26.08
Forfeited	(189	)	35.37		(48	)	35.37
Unvested at December 31, 2016	46,499		27.58		856,877		26.99
Granted	19,442		29.85		310,551		31.80
Vested	(23,430	)	30.47		(257,124	)	28.27
Forfeited	(1,184	)	32.65		(205	)	32.49
Unvested at December 31, 2017	41,327		$	26.92	910,099		$	28.28

The weighted-average grant date fair value for Restricted Shares and LTIP Units granted for the year ended December 31, 2017 and the year ended December 31, 2016 were $31.69 and $34.34, respectively. As of December 31, 2017, there was $14.3 million of total unrecognized compensation cost related to unvested share-based compensation arrangements granted under the Share Incentive Plan. That cost is expected to be recognized over a weighted-average period of 2.2 years. The total fair value of Restricted Shares that vested for each of the year ended December 31, 2017 and the year ended December 31, 2016, was $0.7 million. The total fair value of LTIP Units that vested during the year ended December 31, 2017 and the year ended December 31, 2016, was $7.3 million and $13.6 million, respectively.

Other Plans

On a combined basis, the Company incurred a total of $0.2 million related to the following employee benefit plans for each of the years ended December 31, 2017 and 2016, respectively:

Employee Share Purchase Plan

The Acadia Realty Trust Employee Share Purchase Plan (the “Purchase Plan”), allows eligible employees of the Company to purchase Common Shares through payroll deductions. The Purchase Plan provides for employees to purchase Common Shares on a quarterly basis at a 15% discount to the closing price of the Company’s Common Shares on either the first day or the last day of the quarter, whichever is lower. A participant may not purchase more the $25,000 in Common Shares per year. Compensation expense will be recognized by the Company to the extent of the above discount to the closing price of the Common Shares with respect to the applicable quarter. During the years ended December 31, 2017 and 2016, a total of 4,514 and 4,016 Common Shares, respectively, were purchased by employees under the Purchase Plan.

Deferred Share Plan

During May of 2006, the Company adopted a Trustee Deferral and Distribution Election, under which the participating Trustees earn deferred compensation.

Employee 401(k) Plan

The Company maintains a 401(k) plan for employees under which the Company currently matches 50% of a plan participant’s contribution up to 6% of the employee’s annual salary. A plan participant may contribute up to a maximum of 15% of their compensation, up to $18,000, for the year ended December 31, 2017.

Federal Income Taxes

12 Months Ended

Dec. 31, 2017

Income Tax Disclosure [Abstract]

Federal Income Taxes

The Company has elected to qualify as a REIT in accordance with Sections 856 through 860 of the Code, and intends at all times to qualify as a REIT under the Code. To qualify as a REIT, the Company must meet a number of organizational and operational requirements, including a requirement that it currently distribute at least 90% of its annual REIT taxable income to its shareholders. As a REIT, the Company generally will not be subject to corporate Federal income tax, provided that distributions to its shareholders equal at least the amount of its REIT taxable income as defined under the Code. As the Company distributed sufficient taxable income for the years ended December 31, 2017, 2016 and 2015, no U.S. Federal income or excise taxes were incurred. If the Company fails to qualify as a REIT in any taxable year, it will be subject to Federal income taxes at the regular corporate rates (including any applicable alternative minimum tax) and may not be able to qualify as a REIT for the four subsequent taxable years. Even though the Company qualifies for taxation as a REIT, the Company is subject to certain state and local taxes on its income and property and Federal income and excise taxes on any undistributed taxable income. In addition, taxable income from non-REIT activities managed through the Company’s TRS’s is subject to Federal, state and local income taxes. For taxable years beginning after 2017, no more than 20% of the value of our total assets may consist of the securities of one or more taxable REIT subsidiaries.

In the normal course of business, the Company or one or more of its subsidiaries is subject to examination by Federal, state and local jurisdictions as well as certain jurisdictions outside the United States, in which it operates, where applicable. The Company expects to recognize interest and penalties related to uncertain tax positions, if any, as income tax expense. For the three years ended December 31, 2017, the Company recognized no material adjustments regarding its tax accounting treatment for uncertain tax provisions. As of December 31, 2017, the tax years that remain subject to examination by the major tax jurisdictions under applicable statutes of limitations are generally the year 2014 and forward.

Reconciliation of Net Income to Taxable Income

Reconciliation of GAAP net income attributable to Acadia to taxable income is as follows:



	Year Ended December 31,
(in thousands)	2017			2016			2015

Net income attributable to Acadia	$	61,470		$	72,776		$	65,708
Deferred cancellation of indebtedness income	2,050			2,050			2,050
Deferred rental and other income ^(a)	(934		)	1,610			82
Book/tax difference - depreciation and amortization ^(a)	21,334			15,189			9,983
Straight-line rent and above- and below-market rent adjustments ^(a)	(10,559		)	(7,882		)	(8,041		)
Book/tax differences - equity-based compensation	5,325			10,307			5,833
Joint venture equity in earnings, net ^(a)	9,114			(2,011		)	5,776
Impairment charges and reserves	—			769			(714		)
Acquisition costs ^(a)	1,135			5,116			1,190
Gains	(5,181		)	—			(760		)
Book/tax differences - miscellaneous	930			(4,924		)	2,573
Taxable income	$	84,684		$	93,000		$	83,680
Distributions declared	$	87,848		$	91,053		$	84,683

__________


(a)	Adjustments from certain subsidiaries and affiliates, which are consolidated for financial reporting but not for tax reporting, are included in the reconciliation item "Joint venture equity in earnings, net."

Characterization of Distributions

The Company has determined that the cash distributed to the shareholders for the periods presented is characterized as follows for Federal income tax purposes:



	Year Ended December 31,
	2017				2016				2015
	Per Share		%		Per Share		%		Per Share		%
Ordinary income	$	0.82	78	%	$	0.77	66	%	$	0.83	68	%
Qualified dividend	—		—	%	—		—	%	—		—	%
Capital gain	0.23		22	%	0.39		34	%	0.39		32	%
Total	$	1.05	100	%	$	1.16	100	%	$	1.22	100	%

Taxable REIT Subsidiaries

Income taxes have been provided for using the liability method as required by ASC Topic 740, “Income Taxes.” The Company’s TRS income and provision for income taxes associated with the TRS for the periods presented are summarized as follows (in thousands):



	Year Ended December 31,
	2017			2016			2015
TRS income (loss) before income taxes	$	(3,604	)	$	(1,583	)	$	1,008
(Provision) benefit for income taxes:
Federal	(982		)	378			(526		)
State and local	423			97			(134		)
TRS net income (loss) before noncontrolling interests	(4,163		)	(1,108		)	348
Noncontrolling interests	8			(9		)	(208		)
TRS net income (loss)	$	(4,155	)	$	(1,117	)	$	140

The income tax provision for the Company differs from the amount computed by applying the statutory Federal income tax rate to income before income taxes as follows. Amounts are not adjusted for temporary book/tax differences (in thousands):



	Year Ended December 31,
	2017			2016			2015
Federal tax provision (benefit) at statutory tax rate	$	(1,225	)	$	(538	)	$	343
TRS state and local taxes, net of Federal benefit	(190		)	(84		)	53
Tax effect of:
Permanent differences, net	1,131			1,663			396
Prior year (over) under-accrual, net	(1,541		)	—			938
Effect of Tax Cuts and Jobs Act	1,982			—			—
Other	404			(1,516		)	(131		)
REIT state and local income and franchise taxes	443			370			188
Total provision (benefit) for income taxes	$	1,004		$	(105	)	$	1,787

As of December 31, 2017, and 2016, the Company’s deferred tax assets (net of applicable reserves) in its taxable REIT subsidiaries consisted of the following: additional tax basis in RCP investments of $1.0 million and $1.7 million, deferred interest of $0 and $0.8 million and net operating loss carryovers of $1.1 million and $1.3 million, respectively.

Earnings Per Common Share

12 Months Ended

Dec. 31, 2017

Earnings Per Share [Abstract]

Earnings Per Common Share

Basic earnings per Common Share is computed by dividing net income attributable to Common Shareholders by the weighted average Common Shares outstanding. During the periods presented, the Company had unvested LTIP Units which provide for non-forfeitable rights to dividend equivalent payments. Accordingly, these unvested LTIP Units are considered participating securities and are included in the computation of basic earnings per Common Share pursuant to the two-class method.

Diluted earnings per Common Share reflects the potential dilution of the conversion of obligations and the assumed exercises of securities including the effects of restricted share units (“Restricted Share Units”) and share option awards issued under the Company’s Share Incentive Plans (Note 13). The effect of such shares is excluded from the calculation of earnings per share when anti-dilutive as indicated in the table below.

The effect of the conversion of Common OP Units is not reflected in the computation of basic and diluted earnings per share, as they are exchangeable for Common Shares on a one-for-one basis. The income allocable to such units is allocated on this same basis and reflected as noncontrolling interests in the accompanying consolidated financial statements. As such, the assumed conversion of these units would have no net impact on the determination of diluted earnings per share.



	Year Ended December 31,
(dollars in thousands)	2017			2016			2015
Numerator:
Net income attributable to Acadia	$	61,470		$	72,776		$	65,708
Less: net income attributable to participating securities	(642		)	(793		)	(927		)
Income from continuing operations net of income attributable to participating securities	$	60,828		$	71,983		$	64,781

Denominator:
Weighted average shares for basic earnings per share	83,682,789			76,231,000			68,851,083
Effect of dilutive securities:
Employee unvested restricted shares	2,682			12,550			18,556
Denominator for diluted earnings per share	83,685,471			76,243,550			68,869,639

Basic and diluted earnings per Common Share from continuing operations attributable to Acadia	$	0.73		$	0.94		$	0.94

Anti-Dilutive Shares Excluded from Denominator:
Series A Preferred OP Units	188			188			188
Series A Preferred OP Units - Common share equivalent	25,067			25,067			25,067

Series C Preferred OP Units	136,593			141,593			—
Series C Preferred OP Units - Common share equivalent	479,978			410,207			—

Summary of Quarterly Financial Information (Unaudited)

12 Months Ended

Dec. 31, 2017

Quarterly Financial Information Disclosure [Abstract]

Summary of Quarterly Financial Information (Unaudited)

The quarterly results of operations of the Company for the years ended December 31, 2017 and 2016 are as follows (in thousands, except per share amounts):



	Three Months Ended ^(a,b,c,d)
	March 31, 2017			June 30, 2017		September 30, 2017			December 31, 2017
Revenues	$	61,999		$	59,504	$	62,678		$	66,081
Net income	19,971			6,108		13,285			24,944
Net (income) loss attributable to noncontrolling interests	(4,340		)	5,952		(418		)	(4,032		)
Net income attributable to Acadia	15,631			12,060		12,867			20,912

Earnings per share attributable to Acadia:
Basic	$	0.18		$	0.14	$	0.15		$	0.25
Diluted	0.18			0.14		0.15			0.25

Weighted average number of shares:
Basic	83,635			83,662		83,700			83,733
Diluted	83,646			83,662		83,700			83,733

Cash dividends declared per Common Share	$	0.26		$	0.26	$	0.26		$	0.27

__________


(a)	The three months ended March 31, 2017 includes the Company’s $2.7 million proportionate share of aggregate gains of $14.5 million on the sales of two unconsolidated properties (Note 4).


(b)	The three months ended June 30, 2017 includes the Company’s $0.8 million proportionate share of a $3.3 million gain on sale of an unconsolidated property (Note 4).


(c)	The three months ended September 30, 2017 includes an aggregate $13.0 million gain on the sales of two consolidated properties (Note 2), of which $10.7 million was attributable to noncontrolling interests as well as an impairment charge of $3.8 million, inclusive of an amount attributable to a noncontrolling interest of $2.7 million (Note 8).


(d)	The three months ended December 31, 2017 includes a $5.6 million gain on change in control of interests (Note 4), an aggregate $35.9 million gain on the sales of three consolidated properties (Note 2), of which $26.7 million was attributable to noncontrolling interests; and an impairment charge of $10.6 million, of which $7.6 million was attributable to noncontrolling interests (Note 8).



	Three Months Ended ^{(a, b, c, d)}
	March 31, 2016			June 30, 2016			September 30, 2016		December 31, 2016
Revenues	$	48,045		$	43,918		$	43,855	$	54,121
Net income	73,875			26,155			326		34,236
Net (income) loss attributable to noncontrolling interests	(44,950		)	(8,237		)	5,786		(14,415		)
Net income attributable to Acadia	28,925			17,918			6,112		19,821
Earnings per share attributable to Acadia:
Basic	$	0.40		$	0.24		$	0.08	$	0.24
Diluted	0.40			0.24			0.08		0.24

Weighted average number of shares:
Basic	70,756			72,896			78,449		82,728
Diluted	71,215			72,896			78,624		82,728

Cash dividends declared per Common Share	$	0.25		$	0.25		$	0.25	$	0.41

__________


(a)	The three months ended March 31, 2016 includes Fund III's $65.4 million gain on sale of its 65% consolidated interest in Cortlandt Town Center of which $49.4 million was attributable to noncontrolling interests (Note 2).


(b)	The three months ended June 30, 2016 includes a $16.6 million gain on sale of Fund III's consolidated Heritage Shops property of which $12.5 million was attributable to noncontrolling interests (Note 2).


(c)	The three months ended June 30, 2016, September 30, 2016 and December 31, 2016 reflect the impact of the de-consolidation of the Company's investment in the Brandywine portfolio, which was effective May 1, 2016 (Note 4).


(d)	The three months ended December 31, 2016 reflect the impact of an out-of-period adjustment resulting in a net decrease to net income of $4.2 million, of which $1.6 million was attributable to noncontrolling interests (Note 1).

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2017
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Acquisition On February 21, 2018, Fund V acquired a shopping center located in Trussville, Alabama for $45.2 million. It is not practicable to disclose the preliminary purchase price allocation or consolidated pro forma financial information for this transaction given the short period of time between the acquisition date and the filing of this Report. Financings On January 24, 2018, Fund V obtained mortgage financing of $22.9 million for its recently acquired Plaza Santa Fe property (Note 2). On January 29, 2018, Fund V obtained mortgage financing of $16.9 million for its recently acquired New Towne Plaza property (Note 2). On February 20, 2018, the Company completed a $500.0 million senior unsecured credit facility (the “Credit Facility”), comprised of a $150.0 million senior unsecured revolving credit facility (the “Revolver”), and a $350.0 million senior unsecured term loan (the “Term Loan”). The Credit Facility refinanced the Company’s existing $300.0 million credit facility (comprised of the $150.0 million Core unsecured revolving line of credit and the $150.0 million term loan), $150.0 million in Core unsecured term loans (Note 7) and repaid a $40.4 million mortgage secured by its 664 North Michigan Property. The Revolver and Term Loans mature on March 31, 2022 and March 31, 2023, respectively. Dispositions On January 18, 2018, Fund IV’s Broughton Street Portfolio venture (Note 4) sold its 108 W. Broughton and 110 W. Broughton Street properties for a total of $8.0 million. Structured Financing On January 24, 2018, the Company received full settlement of one of its Core notes receivable with a principal amount of $26.0 million (Note 3). Other On February 20, 2018, the Company’s Board of Trustees elected to terminate the existing repurchase program and authorized a new Common Share repurchase program under which the Company may repurchase, from time to time, up to a maximum of $200.0 million of its common shares. The shares may be repurchased in the open market or in privately negotiated transactions. The common share repurchase program does not obligate the Company to repurchase any specific number of shares and may be suspended or terminated at any time at the Company’s discretion without prior notice.

SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS

12 Months Ended

Dec. 31, 2017

Valuation and Qualifying Accounts [Abstract]

SCHEDULE II-VALUATION AND QUALIFYING ACCOUNTS



	Balance at Beginning of Year		Charged to Expenses		Adjustments to Valuation Accounts		Deductions			Balance at End of Year

Year ended December 31, 2017:
Allowance for deferred tax asset	$	859	$	—	$	671	$	—		$	1,530
Allowance for uncollectible accounts	5,720		200		—		—			5,920
Allowance for notes receivable	—		—		—		—			—
Year ended December 31, 2016:
Allowance for deferred tax asset	—		—		859		—			859
Allowance for uncollectible accounts	7,451		—		—		(1,731		)	5,720
Allowance for notes receivable	—		—		—		—			—
Year ended December 31, 2015:
Allowance for deferred tax asset	—		—		—		—			—
Allowance for uncollectible accounts	5,952		1,499		—		—			7,451
Allowance for notes receivable	—		—		—		—			—

SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION

12 Months Ended

Dec. 31, 2017

SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract]

Schedule III - Real Estate and Accumulated Depreciation



		Initial Cost to Company			Amount at Which Carried at December 31, 2017
Description and Location	Encumbrances	Land	Buildings & Improvements	Increase (Decrease) in Net Investments	Land	Buildings & Improvements	Total	Accumulated Depreciation	Date of Acquisition (a) Construction (c)		Life on which Depreciation in Latest Statement of Income is Compared

Core Portfolio:
Crescent Plaza Brockton, MA	—	1,147	7,425	3,194	1,147	10,619	11,766	7,749	1993	(a)	40 years
New Loudon Center Latham, NY	—	505	4,161	14,118	505	18,279	18,784	14,486	1993	(a)	40 years
Mark Plaza Edwardsville, PA	—	—	3,396	—	—	3,396	3,396	2,934	1993	(c)	40 years
Plaza 422 Lebanon, PA	—	190	3,004	2,765	190	5,769	5,959	5,192	1993	(c)	40 years
Route 6 Mall Honesdale, PA	—	1,664	—	12,446	1,664	12,446	14,110	9,234	1994	(c)	40 years
Abington Towne Center Abington, PA	—	799	3,197	2,870	799	6,067	6,866	3,890	1998	(a)	40 years
Bloomfield Town Square Bloomfield Hills, MI	—	3,207	13,774	23,557	3,207	37,331	40,538	21,396	1998	(a)	40 years
Elmwood Park Shopping Center Elmwood Park, NJ	—	3,248	12,992	15,857	3,798	28,299	32,097	19,237	1998	(a)	40 years
Merrillville Plaza Hobart, IN	—	4,288	17,152	5,661	4,288	22,813	27,101	12,260	1998	(a)	40 years
Marketplace of Absecon Absecon, NJ	—	2,573	10,294	4,900	2,577	15,190	17,767	8,107	1998	(a)	40 years
239 Greenwich Avenue Greenwich, CT	27,000	1,817	15,846	1,032	1,817	16,878	18,695	7,830	1998	(a)	40 years
Hobson West Plaza Naperville, IL	—	1,793	7,172	1,983	1,793	9,155	10,948	5,095	1998	(a)	40 years
Village Commons Shopping Center Smithtown, NY	—	3,229	12,917	4,265	3,229	17,182	20,411	9,389	1998	(a)	40 years
Town Line Plaza Rocky Hill, CT	—	878	3,510	7,736	907	11,217	12,124	9,062	1998	(a)	40 years
Branch Shopping Center Smithtown, NY	—	3,156	12,545	15,935	3,401	28,235	31,636	11,247	1998	(a)	40 years
Methuen Shopping Center Methuen, MA	—	956	3,826	1,260	961	5,081	6,042	2,518	1998	(a)	40 years
The Gateway Shopping Center South Burlington, VT	—	1,273	5,091	12,262	1,273	17,353	18,626	9,521	1999	(a)	40 years
Mad River Station Dayton, OH	—	2,350	9,404	2,102	2,350	11,506	13,856	5,597	1999	(a)	40 years
Pacesetter Park Shopping Center Ramapo, NY	—	1,475	5,899	3,602	1,475	9,501	10,976	4,976	1999	(a)	40 years
Brandywine Holdings Wilmington, DE	26,250	5,063	15,252	2,495	5,201	17,609	22,810	6,796	2003	(a)	40 years
Bartow Avenue Bronx, NY	—	1,691	5,803	1,184	1,691	6,987	8,678	2,958	2005	(c)	40 years
Amboy Road Staten Island, NY	—	—	11,909	2,483	—	14,392	14,392	6,564	2005	(a)	40 years
Chestnut Hill Philadelphia, PA	—	8,289	5,691	4,509	8,289	10,200	18,489	3,877	2006	(a)	40 years
2914 Third Avenue Bronx, NY	—	11,108	8,038	4,768	11,855	12,059	23,914	2,757	2006	(a)	40 years
West Shore Expressway Staten Island, NY	—	3,380	13,499	—	3,380	13,499	16,879	4,114	2007	(a)	40 years
West 54th Street Manhattan, NY	—	16,699	18,704	1,236	16,699	19,940	36,639	5,480	2007	(a)	40 years
5-7 East 17th Street Manhattan, NY	—	3,048	7,281	5,183	3,048	12,464	15,512	2,426	2008	(a)	40 years
651-671 W Diversey Chicago, IL	—	8,576	17,256	8	8,576	17,264	25,840	2,841	2011	(a)	40 years
15 Mercer Street New York, NY	—	1,887	2,483	—	1,887	2,483	4,370	404	2011	(a)	40 years
4401 White Plains Bronx, NY	—	1,581	5,054	—	1,581	5,054	6,635	800	2011	(a)	40 years
Chicago Street Retail Portfolio	—	17,527	49,501	5,544	17,565	55,007	72,572	11,383	2012	(a)	40 years



		Initial Cost to Company			Amount at Which Carried at December 31, 2017
Description and Location	Encumbrances	Land	Buildings & Improvements	Increase (Decrease) in Net Investments	Land	Buildings & Improvements	Total	Accumulated Depreciation	Date of Acquisition (a) Construction (c)		Life on which Depreciation in Latest Statement of Income is Compared
1520 Milwaukee Avenue Chicago, IL	—	2,110	1,306	2	2,110	1,308	3,418	193	2012	(a)	40 years
330-340 River St Cambridge, MA	11,644	8,404	14,235	—	8,404	14,235	22,639	2,179	2012	(a)	40 years
Rhode Island Place Shopping Center Washington, D.C.	—	7,458	15,968	1,708	7,458	17,676	25,134	2,709	2012	(a)	40 years
930 Rush Street Chicago, IL	—	4,933	14,587	—	4,933	14,587	19,520	2,097	2012	(a)	40 years
28 Jericho Turnpike Westbury, NY	14,402	6,220	24,416	—	6,220	24,416	30,636	3,575	2012	(a)	40 years
181 Main Street Westport, CT	—	1,908	12,158	333	1,908	12,491	14,399	1,612	2012	(a)	40 years
83 Spring Street Manhattan, NY	—	1,754	9,200	—	1,754	9,200	10,954	1,265	2012	(a)	40 years
60 Orange Street Bloomfield, NJ	7,522	3,609	10,790	—	3,609	10,790	14,399	1,562	2012	(a)	40 years
179-53 & 1801-03 Connecticut Avenue Washington, D.C.	—	11,690	10,135	802	11,690	10,937	22,627	1,522	2012	(a)	40 years
639 West Diversey Chicago, IL	—	4,429	6,102	779	4,429	6,881	11,310	1,069	2012	(a)	40 years
664 North Michigan Chicago, IL	40,584	15,240	65,331	—	15,240	65,331	80,571	7,973	2013	(a)	40 years
8-12 E. Walton Chicago, IL	—	5,398	15,601	939	5,398	16,540	21,938	1,879	2013	(a)	40 years
3200-3204 M Street Washington, DC	—	6,899	4,249	168	6,899	4,417	11,316	547	2013	(a)	40 years
868 Broadway Manhattan, NY	—	3,519	9,247	5	3,519	9,252	12,771	942	2013	(a)	40 years
313-315 Bowery Manhattan, NY	—	—	5,516	—	—	5,516	5,516	893	2013	(a)	40 years
120 West Broadway Manhattan, NY	—	—	32,819	1,116	—	33,935	33,935	2,192	2013	(a)	40 years
11 E. Walton Chicago, IL	—	16,744	28,346	192	16,744	28,538	45,282	2,923	2014	(a)	40 years
61 Main St. Westport, CT	—	4,578	2,645	182	4,578	2,827	7,405	307	2014	(a)	40 years
865 W. North Avenue Chicago, IL	—	1,893	11,594	23	1,893	11,617	13,510	1,105	2014	(a)	40 years
152-154 Spring St. Manhattan, NY	—	8,544	27,001	—	8,544	27,001	35,545	2,509	2014	(a)	40 years
2520 Flatbush Ave Brooklyn, NY	—	6,613	10,419	193	6,613	10,612	17,225	1,026	2014	(a)	40 years
252-256 Greenwich Avenue Greenwich, CT	—	10,175	12,641	119	10,175	12,760	22,935	1,300	2014	(a)	40 years
Bedford Green Bedford Hills, NY	—	12,425	32,730	1,929	12,425	34,659	47,084	3,228	2014	(a)	40 years
131-135 Prince Street Manhattan, NY	—	—	57,536	135	—	57,671	57,671	8,969	2014	(a)	40 years
Shops at Grand Ave Queens, NY	—	20,264	33,131	312	20,264	33,443	53,707	2,746	2014	(a)	40 years
201 Needham St. Newton, MA	—	4,550	4,459	105	4,550	4,564	9,114	419	2014	(a)	40 years
City Center San Francisco, CA	—	36,063	109,098	2,604	36,063	111,702	147,765	7,731	2015	(a)	40 years
163 Highland Avenue Needham, MA	9,112	12,679	11,213	—	12,679	11,213	23,892	911	2015	(a)	40 years
Roosevelt Galleria Chicago, IL	—	4,838	14,574	—	4,838	14,574	19,412	856	2015	(a)	40 years
Route 202 Shopping Center Wilmington, DE	—	—	6,346	13	—	6,359	6,359	467	2015	(a)	40 years
991 Madison Avenue New York, NY	—	—	76,965	175	—	77,140	77,140	2,749	2016	(a)	40 years
165 Newbury Street Boston, MA	—	1,918	3,980	—	1,918	3,980	5,898	166	2016	(a)	40 years
Concord & Milwaukee Chicago, IL	2,802	2,739	2,746	—	2,739	2,746	5,485	103	2016	(a)	40 years
State & Washington Chicago, IL	24,974	3,907	70,943	—	3,907	70,943	74,850	2,365	2016	(a)	40 years



		Initial Cost to Company			Amount at Which Carried at December 31, 2017
Description and Location	Encumbrances	Land	Buildings & Improvements	Increase (Decrease) in Net Investments	Land	Buildings & Improvements	Total	Accumulated Depreciation	Date of Acquisition (a) Construction (c)		Life on which Depreciation in Latest Statement of Income is Compared
151 N. State Street Chicago, IL	14,179	1,941	25,529	—	1,941	25,529	27,470	904	2016	(a)	40 years
North & Kingsbury Chicago, IL	12,931	18,731	16,292	—	18,731	16,292	35,023	564	2016	(a)	40 years
Sullivan Center Chicago, IL	—	13,443	137,327	54	13,443	137,381	150,824	4,578	2016	(a)	40 years
California & Armitage Chicago, IL	2,622	6,770	2,292	2	6,770	2,294	9,064	84	2016	(a)	40 years
555 9th Street San Francisco, CA	60,000	75,591	73,268	—	75,591	73,268	148,859	2,154	2016	(a)	40 years
Market Square Wilmington, DE	—	8,100	31,221	157	8,100	31,379	39,479	75	2017	(a)	40 years
Undeveloped Land	—	100	—	—	100	—	100	—
Fund II:
City Point Brooklyn, NY	224,820	—	100,316	455,125	—	555,441	555,441	13,628	2007	(c)	40 years
Fund III:
654 Broadway Manhattan, NY	—	9,040	3,654	2,883	9,040	6,537	15,577	921	2011	(a)	40 years
640 Broadway Manhattan, NY	49,470	12,503	19,960	12,921	12,503	32,881	45,384	4,694	2012	(a)	40 years
3104 M St. Washington, DC	4,419	750	2,115	5,139	750	7,254	8,004	283	2013	(c)	40 years
3780-3858 Nostrand Avenue Brooklyn, NY	10,617	6,229	11,216	6,139	6,229	17,355	23,584	2,157	2013	(a)	40 years
Fund IV:				—			—
210 Bowery Manhattan, NY	10,919	1,875	5,625	17,104	1,875	22,729	24,604	142	2012	(c)	40 years
Paramus Plaza Paramus, NJ	18,454	11,052	7,037	11,560	11,052	18,597	29,649	1,739	2013	(a)	40 years
Lake Montclair Center Dumfries, VA	14,098	7,077	12,028	702	7,077	12,730	19,807	1,482	2013	(a)	40 years
938 W. North Avenue Chicago, IL	14,100	2,314	17,067	2,044	2,314	19,111	21,425	1,733	2013	(a)	40 years
27 E. 61st Street Manhattan, NY	—	4,813	14,438	6,693	4,813	21,131	25,944	131	2014	(c)	40 years
17 E. 71st Street Manhattan, NY	19,000	7,391	20,176	266	7,391	20,442	27,833	1,680	2014	(a)	40 years
Broughton St. Portfolio Savannah, GA	24,699	—	—	—	—	—	—	—	2014	(c)	40 years
1035 Third Ave Manhattan, NY	41,387	12,759	37,431	4,648	14,099	40,739	54,838	2,992	2015	(a)	40 years
801 Madison Avenue Manhattan, NY	—	4,178	28,470	4,474	4,178	32,945	37,123	206	2015	(c)	40 years
2208-2216 Fillmore Street San Francisco, CA	5,606	3,027	6,376	26	3,027	6,402	9,429	348	2015	(a)	40 years
146 Geary Street San Francisco, CA	27,700	9,500	28,500	7	9,500	28,507	38,007	1,544	2015	(a)	40 years
2207 Fillmore Street San Francisco, CA	1,120	1,498	1,735	119	1,498	1,854	3,352	93	2015	(a)	40 years
1861 Union St. San Francisco, CA	2,315	2,188	1,293	8	2,188	1,301	3,489	67	2015	(a)	40 years
1964 Union Street San Francisco, CA	1,463	563	1,688	2,577	563	4,265	4,828	44	2016	(c)	40 years
Restaurants at Fort Point Boston, MA	6,425	1,041	10,905	—	1,041	10,905	11,946	545	2016	(a)	40 years
Wakeforest Crossing Wake Forest, NC	24,000	7,570	24,829	196	7,570	25,025	32,595	989	2016	(a)	40 years
Airport Mall Bangor, ME	5,613	2,294	7,067	74	2,294	7,141	9,435	278	2016	(a)	40 years
Colonie Plaza Albany, NY	11,890	2,852	9,619	4	2,852	9,623	12,475	338	2016	(a)	40 years
Dauphin Plaza Harrisburg, PA	10,270	5,290	9,464	317	5,290	9,781	15,071	351	2016	(a)	40 years
JFK Plaza Waterville, ME	4,490	751	5,991	7	751	5,998	6,749	222	2016	(a)	40 years
Mayfair Shopping Center Philadelphia, PA	—	6,178	9,266	32	6,178	9,298	15,476	294	2016	(a)	40 years
Shaw's Plaza Waterville, ME	8,035	828	11,814	—	828	11,814	12,642	388	2016	(a)	40 years



				Initial Cost to Company						Amount at Which Carried at December 31, 2017
Description and Location	Encumbrances			Land		Buildings & Improvements		Increase (Decrease) in Net Investments		Land		Buildings & Improvements		Total		Accumulated Depreciation		Date of Acquisition (a) Construction (c)		Life on which Depreciation in Latest Statement of Income is Compared
Wells Plaza Wells, ME	3,368			1,892		2,585		—		1,892		2,585		4,477		124		2016	(a)	40 years
717 N. Michigan Chicago, IL	18,199			20,674		10,093		—		20,674		10,093		30,767		270		2016	(c)	40 years
Shaw's Plaza North Windham, ME	5,988			1,876		6,696		—		1,876		6,696		8,572		94		2017	(a)	40 years
Lincoln Place Fairview Heights, IL	23,100			7,149		22,201		55		7,149		22,256		29,405		545		2017	(a)	40 years
Fund V:
Plaza Santa Fe Santa Fe, NM	—			—		28,214		—		—		28,214		28,214		452		2017	(a)	40 years
Hickory Ridge Hickory, NC	28,613			7,852		29,998		—		7,852		29,998		37,850		312		2017	(a)	40 years
New Towne Plaza Canton, MI	—			5,040		17,391		1		5,040		17,392		22,432		208		2017	(a)	40 years
Fairlane Green Allen Park, MI	—			18,121		37,626		—		18,121		37,626		55,747		—		2017	(a)	40 years

Real Estate Under Development	47,061			88,108		31,473		54,122		88,108		85,594		173,702		—
Debt of Assets Held for Sale	—			—		—		—		—		—		—		—
Unamortized Loan Costs	(12,943		)	—		—		—		—		—		—		—
Unamortized Premium	856			—		—		—		—		—		—		—
Total	$	909,174		$	743,847	$	1,960,389	$	762,245	$	746,943	$	2,719,539	$	3,466,482	$	339,862

Notes:


1.	Depreciation on buildings and improvements reflected in the consolidated statements of income is calculated over the estimated useful life of the assets as follows: Buildings at 40 years and improvements at the shorter of lease term or useful life.


2.	The aggregate gross cost of property included above for Federal income tax purposes was approximately $3.4 billion as of December 31, 2017.

The following table reconciles the activity for real estate properties from January 1, 2015 to December 31, 2017 (in thousands):



	Year Ended December 31,
	2017			2016			2015
Balance at beginning of year	$	3,382,000		$	2,736,283		$	2,208,595
Other improvements	55,763			152,129			162,760
Property acquisitions	179,292			761,400			418,396
Property dispositions or held for sale assets	(189,895		)	(134,332		)	(66,359		)
Prior year purchase price allocation adjustments	—			(9,844		)	—
Deconsolidation of previously consolidated investments	—			(123,636		)	—
Consolidation of previously unconsolidated investments	39,322			—			12,891
Balance at end of year	$	3,466,482		$	3,382,000		$	2,736,283

The following table reconciles accumulated depreciation from January 1, 2015 to December 31, 2017 (in thousands):



	Year Ended December 31,
	2017			2016			2015
Balance at beginning of year	$	287,066		$	298,703		$	256,015
Depreciation related to real estate	73,268			49,269			49,775
Property dispositions	(20,472		)	(27,829		)	(7,087		)
Deconsolidation of previously consolidated investments	—			(33,077		)	—
Balance at end of year	$	339,862		$	287,066		$	298,703

SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE

12 Months Ended

Dec. 31, 2017

Mortgage Loans on Real Estate [Abstract]

SCHEDULE IV-MORTGAGE LOANS ON REAL ESTATE



Description	Effective Interest Rate	Final Maturity Date	Face Amount of Notes Receivable		Net Carrying Amount of Notes Receivable as of December 31, 2017
First Mortgage Loan	6.0%	6/1/2018	$	15,000	$	15,000
First Mortgage Loan	LIBOR + 7.1%	6/25/2018	26,000		26,000
First Mortgage Loan	8.1%	4/30/2019	153,400		60,695
Zero Coupon Loan	2.5%	5/31/2020	29,793		31,778
Mezzanine Loan	18.0%	7/1/2020	3,007		5,106
Preferred Equity	15.3%	2/3/2021	14,000		15,250
Total			$	241,200	$	153,829

The Company monitors the credit quality of its notes receivable on an ongoing basis and considers indicators of credit quality such as loan payment activity, the estimated fair value of the underlying collateral, the seniority of the Company's loan in relation to other debt secured by the collateral, the personal guarantees of the borrower and the prospects of the borrower.

The following table reconciles the activity for loans on real estate from January 1, 2015 to December 31, 2017 (in thousands):



	Reconciliation of Loans on Real Estate
	Year Ended December 31,
	2017			2016			2015
Balance at beginning of year	$	276,163		$	147,188		$	102,286
Additions	11,371			171,794			48,500
Disposition of air rights through issuance of notes	—			—			29,539
Repayments	(32,000		)	(42,819		)	(15,984		)
Conversion to real estate through receipt of deed or through foreclosure	(101,705		)	—			(13,386		)
Other	—			—			(3,767		)
Balance at end of year	$	153,829		$	276,163		$	147,188

Organization, Basis of Presentation and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Segments	Segments At December 31, 2017, the Company had three reportable operating segments: Core Portfolio, Funds and Structured Financing. The Company’s chief operating decision maker may review operational and financial data on a property basis and does not differentiate properties on a geographical basis for purposes of allocating resources or capital. Each property is considered a separate operating segment; however, each property on a stand-alone basis represents less than 10% of revenues, profit or loss, and assets of the combined reported operating segment and meets the majority of the aggregations criteria under the applicable standard.
Principles of Consolidation	Noncontrolling Interests Noncontrolling interests represent the portion of equity that the Company does not own in those entities it consolidates. The Company identifies its noncontrolling interests separately within the equity section on the Company’s consolidated balance sheets. The amounts of consolidated net earnings attributable to the Company and to the noncontrolling interests are presented separately on the Company’s consolidated statements of income. Noncontrolling interests also include amounts related to common and preferred OP Units issued to unrelated third parties in connection with certain property acquisitions. In addition, the Company periodically issues common OP Units to certain employees of the Company under its share-based incentive program. Unit holders generally have the right to redeem their units for shares of the Company's common stock subject to blackout and other limitations. Common and restricted OP Units are included in the caption Noncontrolling interest within the equity section on the Company’s consolidated balance sheets. Principles of Consolidation The consolidated financial statements include the consolidated accounts of the Company and its investments in partnerships and limited liability companies in which the Company has control in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 810 “Consolidation” (“ASC Topic 810”). The ownership interests of other investors in these entities are recorded as noncontrolling interests. All significant intercompany balances and transactions have been eliminated in consolidation. Investments in entities for which the Company has the ability to exercise significant influence over, but does not have financial or operating control, are accounted for using the equity method of accounting. Accordingly, the Company’s share of the earnings (or losses) of these entities are included in consolidated net income.
Cost Method Investments	Cost Method Investments The Company has certain investments to which it applies the cost method of accounting. The Company recognizes as income distributions from net accumulated earnings of the investee since the date of acquisition. The net accumulated earnings of an investee subsequent to the date of investment are recognized by the Company only to the extent distributed by the investee. Distributions received in excess of earnings subsequent to the date of investment are considered a return of investment and are recorded as reductions of cost of the investment. For the periods presented, there have been no events or changes in circumstances that may have a significant adverse effect on the fair value of the Company's cost-method investments.
Use of Estimates	Use of Estimates GAAP requires the Company’s management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. The most significant assumptions and estimates relate to the valuation of real estate, depreciable lives, revenue recognition and the collectability of notes receivable and rents receivable. Application of these estimates and assumptions requires the exercise of judgment as to future uncertainties and, as a result, actual results could differ from these estimates.
Real Estate	Real Estate Land, buildings, and personal property are carried at cost less accumulated depreciation. Improvements and significant renovations that extend the useful life of the properties are capitalized, while replacements, maintenance, and repairs that do not improve or extend the lives of the respective assets are expensed as incurred. Real estate under development includes costs for significant property expansion and development. Depreciation is computed on the straight-line basis over estimated useful lives of the assets as follows: Buildings and improvements Useful lives of 40 years for buildings and 15 years for improvements Furniture and fixtures Useful lives, ranging from five years to 20 years Tenant improvements Shorter of economic life or lease terms Purchase Accounting – Upon acquisitions of real estate, the Company assesses the fair value of acquired assets and assumed liabilities (including land, buildings and improvements, and identified intangibles such as above- and below-market leases and acquired in-place leases and customer relationships) and acquired liabilities in accordance with ASC Topic 805, “Business Combinations” and ASC Topic 350 “Intangibles – Goodwill and Other,” and allocates the acquisition price based on these assessments. The Company assesses fair value of its tangible assets acquired and assumed liabilities based on estimated cash flow projections that utilize appropriate discount and capitalization rates and available market information at the measurement period. Estimates of future cash flows are based on a number of factors including the historical operating results, known trends, and market/economic conditions that may affect the property. In determining the value of above- and below-market leases, the Company estimates the present value difference between contractual rent obligations and estimated market rate of leases at the time of the transaction. To the extent there were fixed-rate options at below-market rental rates, the Company included these along with the current term below-market rent in arriving at the fair value of the acquired leases. The discounted difference between contract and market rents is being amortized to rental income over the remaining applicable lease term, inclusive of any option periods. In determining the value of acquired in-place leases and customer relationships, the Company considers market conditions at the time of the transaction and values the costs to execute similar leases during the expected lease-up period from vacancy to existing occupancy, including carrying costs. The value assigned to in-place leases and tenant relationships is amortized over the estimated remaining term of the leases. If a lease were to be terminated prior to its scheduled expiration, all unamortized costs relating to that lease would be written off. The Company estimates the value of any assumption of mortgage debt based on market conditions at the time of acquisitions including prevailing interest rates, terms and ability to obtain financing for a similar asset. Mortgage debt discounts or premiums are amortized into interest expense over the remaining term of the related debt instrument. Real Estate Under Development – The Company capitalizes certain costs related to the development of real estate. Interest and real estate taxes incurred during the period of the construction, expansion or development of real estate are capitalized and depreciated over the estimated useful life of the building. The Company will cease the capitalization of these costs when construction activities are substantially completed and the property is available for occupancy by tenants, but no later than one year from the completion of major construction activity at which time the project is placed in service and depreciation commences. If the Company suspends substantially all activities related to development of a qualifying asset, the Company will cease capitalization of interest and taxes until activities are resumed. Real Estate Impairment – The Company reviews its real estate and real estate under development for impairment when there is an event or a change in circumstances that indicates that the carrying amount may not be recoverable. In cases where the Company does not expect to recover its carrying costs on properties held for use, the Company reduces its carrying costs to fair value. The determination of anticipated undiscounted cash flows is inherently subjective, requiring significant estimates made by management, and considers the most likely expected course of action at the balance sheet date based on current plans, intended holding periods and available market information. If the Company is evaluating the potential sale of an asset, the undiscounted future cash flows analysis is probability-weighted based upon management’s best estimate of the likelihood of the alternative courses of action as of the balance sheet date. Such cash flow projections consider factors such as expected future operating income, trends and prospects, as well as the effects of demand, competition and other factors. If an impairment is indicated, an impairment loss is recognized based on the excess of the carrying amount of the asset over its fair value. See Note 8 for information about impairment charges incurred during the periods presented.
Dispositions of Real Estate	Dispositions of Real Estate – The Company recognizes property sales in accordance with ASC Topic 970 “Real Estate.” Sales of real estate include the sale of land, operating properties and investments in real estate joint ventures. Gains from dispositions are recognized using the full accrual or partial sale methods, provided that various criteria relating to the terms of sale and any subsequent involvement by the Company with the asset sold are met.
Real Estate Held for Sale	Real Estate Held for Sale – The Company generally considers assets to be held for sale when it has entered into a contract to sell the property, all material due diligence requirements have been satisfied, and management believes it is probable that the disposition will occur within one year. Assets that are classified as held for sale are recorded at the lower of their carrying amount or fair value, less cost to sell.
Notes Receivable	Notes Receivable Notes receivable include certain loans that are held for investment and are collateralized by real estate-related investments and may be subordinate to other senior loans. Notes receivable are recorded at stated principal amounts or at initial investment less accretive yield for loans purchased at a discount, which is accreted over the life of the note. The Company defers loan origination and commitment fees, net of origination costs, and amortizes them over the term of the related loan. The Company evaluates the collectability of both principal and interest based upon an assessment of the underlying collateral value to determine whether it is impaired. A reserve is recorded when, based upon current information and events, it is probable that the Company will be unable to collect all amounts due according to the existing contractual terms. The amount of the reserve is calculated by comparing the recorded investment to the value of the underlying collateral. As the underlying collateral for a majority of the notes receivable is real estate-related investments, the same valuation techniques are used to value the collateral as those used to determine the fair value of real estate investments for impairment purposes. Given the small number of notes outstanding, the Company does not provide for an additional reserve based on the grouping of loans, as the Company believes the characteristics of its notes are not sufficiently similar to allow an evaluation of these notes as a group for a possible loan loss allowance. As such, all of the Company’s notes are evaluated individually for this purpose. Interest income on performing notes is accrued as earned. A note is placed on non-accrual status when, based upon current information and events, it is probable that the Company will not be able to collect all amounts due according to the existing contractual terms. Recognition of interest income on an accrual basis on non-performing notes is resumed when it is probable that the Company will be able to collect amounts due according to the contractual terms.
Investments in and Advances to Unconsolidated Joint Ventures	Investments in and Advances to Unconsolidated Joint Ventures Some of the Company’s joint ventures obtain non-recourse third-party financing on their property investments, contractually limiting the Company’s exposure to losses. The Company recognizes income for distributions in excess of its investment where there is no recourse to the Company and no intention or obligation to contribute additional capital. For investments in which there is recourse to the Company or an obligation or intention to contribute additional capital exists, distributions in excess of the investment are recorded as a liability. When characterizing distributions from equity investees within the Company's consolidated statements of cash flows, all distributions received are first applied as returns on investment to the extent there are cumulative earnings related to the respective investment and are classified as cash inflows from operating activities. If cumulative distributions are in excess of cumulative earnings, distributions are considered return of investment. In such cases, the distribution is classified as cash inflows from investing activities. To the extent that the Company’s carrying basis in an unconsolidated affiliate is different from the basis reflected at the joint venture level, the basis difference is amortized over the life of the related assets and included in the Company’s share of equity in net income (loss) of investments in unconsolidated affiliates the joint venture. The Company periodically reviews its investments in unconsolidated joint ventures for other-than-temporary losses in investment value. Any decline that is not expected to be recovered based on the underlying assets of the investment, is considered other than temporary and an impairment charge is recorded as a reduction in the carrying value of the investment. During the periods presented there were no impairment charges related to the Company’s investments in unconsolidated joint ventures.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity of three months or less when purchased to be cash equivalents. Cash and cash equivalents are maintained at financial institutions and, at times, balances may exceed the limits insured by the Federal Deposit Insurance Corporation.
Restricted Cash	Restricted Cash Restricted cash consists principally of cash held for real estate taxes, construction costs, property maintenance, insurance, minimum occupancy and property operating income requirements at specific properties as required by certain loan agreements.
Deferred Costs	Deferred Costs Fees and costs paid in the successful negotiation of leases are deferred and amortized on a straight-line basis over the terms of the respective leases. Fees and costs incurred in connection with obtaining financing are deferred and amortized as a component of interest expense over the term of the related debt obligation on a straight-line basis, which approximates the effective interest method. The Company capitalizes salaries, commissions and benefits related to time spent by leasing and legal department personnel involved in originating leases.
Derivative Instruments and Hedging Activities	Derivative Instruments and Hedging Activities The Company measures derivative instruments at fair value and records them as assets or liabilities, depending on its rights or obligations under the applicable derivative contract. Derivatives that are not designated as hedges must be adjusted to fair value through earnings. For a derivative designated and that qualified as a cash flow hedge, the effective portion of the change in fair value of the derivative is recognized in Other comprehensive (loss) income until the hedged item is recognized in earnings. The ineffective portion of a derivative’s change in fair value is immediately recognized in earnings. Although the Company's derivative contracts are subject to master netting arrangements, which serve as credit mitigants to both the Company and its counterparties under certain situations, the Company does not net its derivative fair values or any existing rights or obligations to cash collateral on the consolidated balance sheets. The Company does not use derivatives for trading or speculative purposes. For the periods presented, all of the Company's derivatives qualified and were designated as cash flow hedges, and none of its derivatives were deemed ineffective.
Revenue Recognition and Accounts Receivable	Revenue Recognition and Accounts Receivable Minimum rents from tenants are recognized using the straight-line method over the non-cancelable lease term of the respective leases. Lease termination fees are recognized upon the effective termination of a tenant’s lease when the Company has no further obligations under the lease. As of December 31, 2017 and 2016, unbilled rents receivable relating to the straight-lining of rents of $37.3 million and $34.9 million, respectively, are included in Rents Receivable, net on the accompanying consolidated balance sheets. Certain of these leases also provide for percentage rents based upon the level of sales achieved by the tenant. Percentage rent is recognized in the period when the tenants’ sales breakpoint is met. In addition, leases typically provide for the reimbursement to the Company of real estate taxes, insurance and other property operating expenses. These reimbursements are recognized as revenue in the period the related expenses are incurred. The Company makes estimates of the uncollectability of its accounts receivable related to tenant revenues. An allowance for doubtful accounts has been provided against certain tenant accounts receivable that are estimated to be uncollectible. Once the amount is ultimately deemed to be uncollectible, it is written off. Rents receivable at December 31, 2017 and 2016 are shown net of an allowance for doubtful accounts of $5.9 million and $5.7 million, respectively.
Stock-Based Compensation	Stock-Based Compensation Stock-based compensation expense for all equity-classified stock-based compensation awards is based on the grant date fair value estimated in accordance with current accounting guidance for share-based payments. The Company recognizes these compensation costs for only those shares or units expected to vest on a straight-line or graded-vesting basis, as appropriate, over the requisite service period of the award. The Company includes stock-based compensation within the Additional paid-in capital caption of equity.
Income Taxes	Income Taxes The Company has made an election to be taxed, and believes it qualifies, as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended (the “Code”). To maintain REIT status for Federal income tax purposes, the Company is generally required to distribute at least 90% of its REIT taxable income to its shareholders as well as comply with certain other income, asset and organizational requirements as defined in the Code. Accordingly, the Company is generally not subject to Federal corporate income tax to the extent that it distributes 100% of its REIT taxable income each year. In connection with the REIT Modernization Act, the Company is permitted to participate in certain activities and still maintain its qualification as a REIT, so long as these activities are conducted in entities that elect to be treated as taxable subsidiaries under the Code. As such, the Company is subject to Federal and state income taxes on the income from these activities. The Protecting Americans from Tax Hikes Act (PATH Act) was enacted in December 2015, and included numerous law changes applicable to REITs. The provisions have various effective dates beginning as early as 2016. These changes did not materially impact the Company's operations or consolidated financial statements. The Tax Cuts and Jobs Act was enacted in December 2017 and is generally effective for tax years beginning in 2018. This new legislation is not expected to have a material adverse effect on the Company’s business and contains several potentially favorable provisions. However, the Company has recorded an reduction of $2.0 million to its deferred tax assets to reflect the lower Federal corporate tax rate and other provisions effective in 2018. Although it may qualify for REIT status for Federal income tax purposes, the Company is subject to state income or franchise taxes in certain states in which some of its properties are located. In addition, taxable income from non-REIT activities managed through the Company’s taxable REIT subsidiaries (“TRS”) is fully subject to Federal, state and local income taxes. The Company accounts for TRS income taxes under the liability method as required by ASC Topic 740, “Income Taxes.” Under the liability method, deferred income taxes are recognized for the temporary differences between the GAAP basis and tax basis of the TRS income, assets and liabilities. The Company records net deferred tax assets to the extent it believes it is more likely than not that these assets will be realized and would record a valuation allowance to reduce deferred tax assets when it has determined that an uncertainty exists regarding their realization, which would increase the provision for income taxes. In making such determination, the Company considers all available positive and negative evidence, including forecasts of future taxable income, the reversal of other existing temporary differences, available net operating loss carry-forwards, tax planning strategies and recent results of operations. Several of these considerations require assumptions and significant judgment about the forecasts of future taxable income and are consistent with the plans and estimates that the Company is utilizing to manage its business. To the extent facts and circumstances change in the future, adjustments to the valuation allowances may be required.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In May 2014, the FASB issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers. ASU 2014-09 is a comprehensive new revenue recognition model requiring a company to recognize revenue to depict the transfer of goods or services to a customer at an amount reflecting the consideration it expects to receive in exchange for those goods or services. ASU 2014-09 does not apply to the Company’s lease revenues, but will apply to reimbursed tenant costs. Additionally, this guidance modifies disclosures regarding the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. In August 2015, the FASB issued ASU 2015-14, which defers the effective date of ASU 2014-09 for all entities by one year, until years beginning in 2018, with early adoption permitted but not before 2017. Entities may adopt ASU 2014-09 using either a full retrospective approach reflecting the application of the standard in each prior reporting period with the option to elect certain practical expedients or a modified retrospective approach with the cumulative effect recognized at the date of adoption. Substantially all of the Company’s revenue is derived from its leases and therefore falls outside of the scope of this guidance. With respect to its fee-derived revenue, the Company does not anticipate any significant changes to the timing of the Company’s revenue recognition; however, the recognition of gains on sales of properties may be impacted prospectively under limited circumstances under which collectability may not be reasonably assured or if the Company has continuing involvement with a sold property. The Company intends to implement the standard using the modified retrospective approach with the cumulative effect recognized in retained earnings at the date of application. In February 2016, the FASB issued ASU No. 2016-02, Leases. ASU 2016-02 outlines a new model for accounting by lessees, whereby their rights and obligations under substantially all leases, existing and new, would be capitalized and recorded on the balance sheet. As a lessee, the Company is party to various equipment, ground, and office leases with future payment obligations aggregating $207.2 million at December 31, 2017 (Note 11) for which the Company expects to record right-of-use assets upon adoption of ASU 2016-02. For lessors, however, the accounting remains largely unchanged from the current model, with the distinction between operating and financing leases retained, but updated to align with certain changes to the lessee model and the new revenue recognition standard discussed above. The new guidance also requires that internal leasing costs be expensed as incurred, as opposed to capitalized and deferred. The Company expects that it will no longer capitalize a significant portion of internal leasing costs that were previously capitalized. The Company capitalized $1.0 million, $1.1 million and $1.4 million of internal leasing costs during the years ended December 31, 2017, 2016 and 2015, respectively. ASU 2016-02 will also require extensive quantitative and qualitative disclosures and is effective beginning after December 15, 2018, but early adoption is permitted. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments – Credit Losses. ASU 2016-13 introduces a new model for estimating credit losses for certain types of financial instruments, including loans receivable, held-to-maturity debt securities, and net investments in direct financing leases, amongst other financial instruments. ASU 2016-13 also modifies the impairment model for available-for-sale debt securities and expands the disclosure requirements regarding an entity’s assumptions, models, and methods for estimating the allowance for losses. ASU 2016-13 is effective for periods beginning after December 15, 2019, with adoption permitted for fiscal years beginning after December 15, 2018. Retrospective adjustments shall be applied through a cumulative-effect adjustment to retained earnings. The adoption of ASU 2016-13 is not expected to have a material impact on the Company’s consolidated financial statements. In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows – Classification of Certain Cash Receipts and Cash Payments. ASU 2016-15 provides guidance on certain specific cash flow issues, including, but not limited to, debt prepayment or extinguishment costs, contingent consideration payments made after a business combination and distributions received from equity method investees. ASU 2016-15 is effective for periods beginning after December 15, 2017, with early adoption permitted and shall be applied retrospectively where practicable. The Company expects to elect the “cumulative distribution approach” whereby distributions received from equity method investments would be classified as cash flows from operations to the extent of equity earnings and then as cash flows from investing activities thereafter. Upon the adoption of ASU 2016-15, the Company expects to reclassify $6.3 million and $0 of its cash inflows from investing activities to cash flows from operating activities in its historical presentation of cash flows related to its equity method investments for the years ended December 31, 2017 and 2016, respectively. In January 2017, the FASB issued ASU No. 2017-01, Business Combinations – Clarifying the Definition of a Business. ASU 2017-01 clarifies that to be considered a business, the elements must include, at a minimum, an input and a substantive process that together significantly contribute to the ability to create output. The new standard illustrates the circumstances under which real estate with in-place leases would be considered a business and provides guidance for the identification of assets and liabilities in purchase accounting. ASU 2017-01 is effective for periods beginning after December 15, 2017 and early adoption is permitted. It is expected that the new standard will reduce the number of future real estate acquisitions that will be accounted for as business combinations and, therefore, reduce the amount of acquisition costs that will be expensed. The Company expensed $2.1 million and $8.2 million of acquisition costs during the year ended December 31, 2017 and 2016, respectively. In January 2017, the FASB issued ASU No. 2017-03 Accounting Changes and Error Corrections (Topic 250) and Investments – Equity Method and Joint Ventures (Topic 323). ASU 2017-03 amends certain SEC guidance in the FASB Accounting Standards Codification in response to SEC staff announcements made during 2016 Emerging Issues Task Force (“EITF”) meetings which addressed (i) the additional qualitative disclosures that a registrant is expected to provide when it cannot reasonably estimate the impact that ASUs 2014-09, 2016-02 and 2016-13 will have in applying the guidance in Staff Accounting Bulletin Topic 11.M and (ii) guidance in ASC 323 related to the amendments made by ASU 2014-01 regarding use of the proportional amortization method in accounting for investments in qualified affordable housing projects (announcement made at the November 17, 2016, EITF meeting). The adoption of ASU 2017-03 is not expected to have a material impact on the Company’s consolidated financial statements. In February 2017, the FASB issued ASU 2017-05, Other Income—Gains and Losses from the Derecognition of Nonfinancial Assets (Subtopic 610-20): Clarifying the Scope of Asset Derecognition Guidance and Accounting for Partial Sales of Nonfinancial Assets, which amends the guidance on nonfinancial assets in ASC 610-20. The amendments clarify that (i) a financial asset is within the scope of ASC 610-20 if it meets the definition of an in substance nonfinancial asset and may include nonfinancial assets transferred within a legal entity to a counter-party, (ii) an entity should identify each distinct nonfinancial asset or in substance nonfinancial asset promised to a counter-party and de-recognize each asset when a counter-party obtains control of it, and (iii) an entity should allocate consideration to each distinct asset by applying the guidance in ASC 606 on allocating the transaction price to performance obligations. Further, ASU 2017-05 provides guidance on accounting for partial sales of nonfinancial assets. The amendments are effective at the same time as the amendments in ASU 2014-09. The adoption of ASU 2017-05 is not expected to have a material impact on the Company's consolidated financial statements. In May 2017, the FASB issued ASU 2017-09, Compensation—Stock Compensation (Topic 718): Scope of Modification Accounting, which clarifies the scope of modification accounting with respect to changes to the terms or conditions of a share-based payment award. Modification accounting would not apply if a change to an award does not affect the total current fair value (or other applicable measurement), vesting conditions, or the classification of the award. For all entities, ASU 2017-09 is effective prospectively for awards modified in fiscal years beginning after December 15, 2017, and interim periods within those annual periods and early adoption is permitted. The adoption of ASU 2017-09 is not expected to have a material impact on the Company's consolidated financial statements because the Company has not historically had significant modifications of its awards. In August 2017, the Financial Accounting Standards Board issued ASU 2017-12, Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities. The purpose of this updated guidance is to better align a company’s financial reporting for hedging activities with the economic objectives of those activities. ASU 2017-12 is effective for fiscal years beginning after December 15, 2018, with early adoption, including adoption in an interim period, permitted. The Company plans to adopt ASU 2017-12 effective January 1, 2018. ASU 2017-12 requires a modified retrospective transition method in which the Company will recognize the cumulative effect of the change on the opening balance of each affected component of equity in the statement of financial position as of the date of adoption. The adoption will not have a material impact on the Company’s consolidated financial statements.

Organization, Basis of Presentation and Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2017

Organization, Consolidation and Presentation of Financial Statements [Abstract]

General terms and operating partnership's equity interests

The following table summarizes the general terms and Operating Partnership’s equity interests in the Funds and Mervyns II (dollars in millions):



Entity	Formation Date	Operating Partnership Share of Capital	Capital Called as of December 31, 2017		Unfunded Commitment		Equity Interest Held By Operating Partnership ^(a)	Preferred Return	Total Distributions as of December 31, 2017 ^(b)
Fund II and Mervyns II	6/2004	28.33%	$	347.1	$	—	28.33%	8%	$	131.6
Fund III	5/2007	24.54%	411.5		38.5		24.54%	6%	551.9
Fund IV	5/2012	23.12%	412.7		117.3		23.12%	6%	131.5
Fund V	8/2016	20.10%	45.8		474.2		20.10%	6%	—

__________


(a)	Amount represents the current economic ownership at December 31, 2017, which could differ from the stated legal ownership based upon the cumulative preferred returns of the respective fund.


(b)	Represents the total for the Funds, including the Operating Partnership and noncontrolling interests’ shares.

Real Estate (Tables)

12 Months Ended

Dec. 31, 2017

Acquisition and Disposition of Properties and Discontinued Operations [Abstract]

Schedule of Consolidated Real Estate

The Company’s consolidated real estate is comprised of the following (in thousands):



	December 31, 2017			December 31, 2016

Land	$	658,835		$	693,252
Buildings and improvements	2,406,488			1,916,288
Tenant improvements	131,850			132,220
Construction in progress	18,642			19,789
Properties under capital lease	76,965			76,965
Total	3,292,780			2,838,514
Less: Accumulated depreciation	(339,862		)	(287,066		)
Operating real estate, net	2,952,918			2,551,448
Real estate under development, at cost	173,702			543,486
Net investments in real estate	$	3,126,620		$	3,094,934

Schedule of Business Acquisitions, by Acquisition

The following table summarizes the allocation of the purchase price of properties acquired during the years ended December 31, 2017 and December 31, 2016 (in thousands):



	Year Ended December 31, 2017			Year Ended December 31, 2016
	Year Ended December 31, 2017			Year Ended December 31, 2016
Net Assets Acquired
Land	$	48,138		$	225,729
Buildings and improvements	173,576			458,525
Other assets	84			3,481
Acquisition-related intangible assets (in Acquired lease intangibles, net)	44,269			63,606
Acquisition-related intangible liabilities (in Acquired lease intangibles, net)	(11,535		)	(72,985		)
Above and below market debt assumed (included in Mortgages and other notes payable, net)	—			(119,601		)
Net assets acquired	$	254,532		$	558,755



Consideration
Cash	$	200,429	$	439,546
Conversion of note receivable	41,010		—
Debt assumed	—		119,209
Liabilities assumed	3,363		—
Existing interest in previously unconsolidated investment	4,159		—
Change in control of previously unconsolidated investment	5,571		—
Total Consideration	$	254,532	$	558,755

During the years ended December 31, 2017 and December 31, 2016, the Company acquired the following consolidated retail properties (dollars in thousands):



Property and Location	Percent Acquired	Date of Acquisition	Purchase Price		Debt Assumed
2017 Acquisitions and Conversions
Core
Market Square Shopping Center - Wilmington, DE (Conversion) (Note 4)	100%	Nov 16, 2017	$	42,800	$	—
Subtotal Core			42,800		—

Fund IV
Lincoln Place - Fairview Heights, IL	100%	Mar 13, 2017	35,350		—
Shaw's Plaza - Windham, ME (Conversion) (Note 3)	100%	Jun 30, 2017	9,142		—
Subtotal Fund IV			44,492		—

Fund V
Plaza Santa Fe - Santa Fe, NM	100%	Jun 5, 2017	35,220		—
Hickory Ridge - Hickory, NC	100%	Jul 27, 2017	44,020		—
New Towne Plaza - Canton, MI	100%	Aug 4, 2017	26,000		—
Fairlane Green - Allen Park, MI	100%	Dec 20, 2017	62,000		—
Subtotal Fund V			167,240		—
Total 2017 Acquisitions and Conversions			$	254,532	$	—

2016 Acquisitions
Core Portfolio
991 Madison Avenue - New York, NY ^(a)	100%	Mar 26, 2016	$	76,628	$	—
165 Newbury Street - Boston, MA	100%	May 13, 2016	6,250		—
Concord & Milwaukee - Chicago, IL	100%	Jul 28, 2016	6,000		2,902
151 North State Street - Chicago, IL	100%	Aug 10, 2016	30,500		14,556
State & Washington - Chicago, IL	100%	Aug 22, 2016	70,250		25,650
North & Kingsbury - Chicago, IL	100%	Aug 29, 2016	34,000		13,409
Sullivan Center - Chicago, IL	100%	Aug 31, 2016	146,939		—
California & Armitage - Chicago, IL	100%	Sep 12, 2016	9,250		2,692
555 9th Street - San Francisco, CA	100%	Nov 2, 2016	139,775		60,000
Subtotal Core Portfolio			519,592		119,209

Fund IV
Restaurants at Fort Point - Boston, MA	100%	Jan 14, 2016	11,500		—
1964 Union Street - San Francisco, CA^(a)	90%	Jan 28, 2016	2,250		1,463
Wake Forest Crossing - Wake Forest, NC	100%	Sep 27, 2016	36,600		—
Airport Mall - Bangor, ME	100%	Oct 28, 2016	10,250		—
Colonie Plaza - Albany, NY	100%	Oct 28, 2016	15,000		—
Dauphin Plaza - Harrisburg, PA	100%	Oct 28, 2016	16,000		—
JFK Plaza - Waterville, ME	100%	Oct 28, 2016	6,500		—
Mayfair Shopping Center - Philadelphia, PA	100%	Oct 28, 2016	16,600		—
Shaw's Plaza - Waterville, ME	100%	Oct 28, 2016	13,800		—
Wells Plaza - Wells, ME	100%	Oct 28, 2016	5,250		—
717 N Michigan - Chicago, IL	100%	Dec 1, 2016	103,500		—
Subtotal Fund IV			237,250		1,463
Total 2016 Acquisitions			$	756,842	$	120,672

__________


(a)	These acquisitions were accounted for as asset acquisitions as the underlying properties did not meet the definition of a business.

Schedule of Property Dispositions

During the years ended December 31, 2017 and December 31, 2016, the Company disposed of the following consolidated properties (in thousands):



Property and Location	Owner	Date Sold	Sale Price		Gain/(Loss) on Sale
2017 Dispositions
New Hyde Park Shopping Center - New Hyde Park, NY	Fund III	Jul 6, 2017	$	22,075	$	6,433
216th Street - New York, NY	Fund II	Sep 11, 2017	30,579		6,543
City Point Condominium Tower I - Brooklyn, NY	Fund II	Oct 13, 2017	96,000		(810		)
1151 Third Avenue - New York, NY	Fund IV	Nov 16, 2017	27,000		5,183
260 E 161st Street - Bronx, NY	Fund II	Dec 13, 2017	105,684		31,537
Total 2017 Dispositions			$	281,338	$	48,886

2016 Dispositions
Cortlandt Town Center (65%) - Mohegan Lake, NY (Note 4)	Fund III	Jan 28, 2016	$	107,250	$	65,393
Heritage Shops - Chicago, IL	Fund III	Apr 26, 2016	46,500		16,572
Total 2016 Dispositions			$	153,750	$	81,965

Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures



	Year Ended December 31,
	2017			2016			2015
Rental revenues	$	13,021		$	16,946		$	31,935
Expenses	(18,964		)	(13,653		)	(27,265		)
Loss on extinguishment of debt	(1,380		)	(81		)	(111		)
(Loss) income from continuing operations of disposed properties before gain on disposition of properties	(7,323		)	3,212			4,559
Gain on disposition of properties, net of tax	48,886			81,965			89,063
Net income attributable to noncontrolling interests	(30,072		)	(70,850		)	(1,732		)
Net income attributable to Acadia	$	11,491		$	14,327		$	91,890

Business Acquisition, Pro Forma Information

The unaudited supplemental pro forma operating data is not necessarily indicative of what the actual results of operations of the Company would have been, assuming the transactions had been completed as set forth above, nor do they purport to represent the Company’s results of operations for future periods.



	Year Ended December 31,
	2017		2016		2015
Pro forma revenues	$	266,485	$	247,843	$	243,237
Pro forma income from continuing operations	21,878		63,681		52,442
Pro forma net income attributable to Acadia	64,107		82,485		58,232
Pro forma basic and diluted earnings per share	0.77		1.02		0.79

Schedule of Development in Process Activities

Development activity for the Company’s consolidated properties comprised the following during the periods presented (dollars in thousands):



	December 31, 2016			Year Ended December 31, 2017						December 31, 2017
	Number of Properties	Carrying Value		Transfers In		Capitalized Costs		Transfers Out		Number of Properties	Carrying Value
Core	1	$	3,499	$	22,422	$	819	$	4,843	2	$	21,897
Fund II	2	443,012		—		6,851		444,955		—	4,908
Fund III	3	50,452		—		22,572		9,085		2	63,939
Fund IV	4	46,523		80,508		2,158		46,231		1	82,958
Total	10	$	543,486	$	102,930	$	32,400	$	505,114	5	$	173,702

- Definition

Tabular disclosure of information related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=65878427&loc=SL51721533-107759

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 4B
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721665-107760

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64827811&loc=d3e1474-107760

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=64827811&loc=d3e1361-107760

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721683-107760

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3A
-URI http://asc.fasb.org/extlink&oid=84176398&loc=SL51724579-110230

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5C
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721675-107760

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 4A
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721663-107760

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84176398&loc=d3e2941-110230

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721673-107760

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 3A
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721659-107760

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5A
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721671-107760

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5D
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721677-107760

+ Details

Notes Receivable, Net (Tables)

12 Months Ended

Dec. 31, 2017

Accounts and Notes Receivable, Net [Abstract]

Schedule of Notes Receivable



	December 31,		December 31,		December 31, 2017
Description	2017		2016		Number	Maturity Date	Interest Rate
Core Portfolio	$	101,695	$	216,400	3	June 2018 - April 2019	6.0% - 8.1%
Fund II	31,778		31,007		1	May 2020	2.5%
Fund III	5,106		4,506		1	July 2020	18.0%
Fund IV	15,250		24,250		1	February 2021	15.3%
	$	153,829	$	276,163	6

Investments in and Advances to Unconsolidated Affiliates (Tables)

12 Months Ended

Dec. 31, 2017

Equity Method Investments and Joint Ventures [Abstract]

Schedule of Equity Method Investments

The Company’s investments in and advances to unconsolidated affiliates consist of the following (dollars in thousands):



		Nominal Ownership Interest	December 31, 2017		December 31, 2016
Fund	Property	December 31, 2017	December 31, 2017		December 31, 2016
Core:
	840 N. Michigan ^(a)	88.43%	$	69,846	$	74,131
	Renaissance Portfolio	20%	35,041		36,437
	Gotham Plaza	49%	29,416		29,421
	Market Square ^{(a, b)}	100%	—		5,469
	Town Center ^{(a, b)}	61.11%	78,801		15,286
	Georgetown Portfolio	50%	3,479		4,287
			216,583		165,031

Mervyns I & II:	KLA/Mervyn's, LLC^(c)	10.5%	—		—

Fund III:
	Fund III Other Portfolio	90%	167		8,108
	Self Storage Management ^(d)	95%	206		241
			373		8,349
Fund IV:
	Broughton Street Portfolio ^(e)	50%	48,335		54,839
	Fund IV Other Portfolio	90%	20,199		21,817
	650 Bald Hill Road	90%	13,609		18,842
			82,143		95,498

Various Funds:	Due from Related Parties ^(f)		2,415		2,193
	Other^(g)		556		957
	Investments in and advances to unconsolidated affiliates		$	302,070	$	272,028

Core:
	Crossroads ^(h)	49%	$	15,292	$	13,691
	Distributions in excess of income from, and investments in, unconsolidated affiliates		$	15,292	$	13,691

__________


(a)	Represents a tenancy-in-common interest.


(b)	During May and November 2017, as discussed below, the Company increased its ownership in Market Square and Town Center, which was formerly included under the caption “Brandywine Portfolio.”


(c)	Distributions have exceeded the Company’s non-recourse investment, therefore the carrying value is zero.


(d)	Represents a variable interest entity.


(e)	The Company is entitled to a 15% return on its cumulative capital contribution which was $15.4 million and $14.5 million at December 31, 2017 and December 31, 2016, respectively. In addition, the Company is entitled to a 9% preferred return on a portion of its equity, which was $36.8 million and $45.4 million at December 31, 2017 and December 31, 2016, respectively.


(f)	Represents deferred fees.


(g)	Includes a cost-method investment in Albertson’s (Note 8) and other investments.


(h)	Distributions have exceeded the Company’s investment; however, the Company recognizes a liability balance as it may be required to fund future obligations of the entity.

Schedule of Condensed Balance Sheet



	December 31,
	2017		2016
Combined and Condensed Balance Sheets
Assets:
Rental property, net	$	518,900	$	576,505
Real estate under development	26,681		18,884
Investment in unconsolidated affiliates	6,853		6,853
Other assets	100,901		75,254
Total assets	$	653,335	$	677,496
Liabilities and partners’ equity:
Mortgage notes payable	$	405,652	$	407,344
Other liabilities	61,932		30,117
Partners’ equity	185,751		240,035
Total liabilities and partners’ equity	$	653,335	$	677,496

Company's share of accumulated equity	$	185,533	$	191,049
Basis differential	95,358		61,827
Deferred fees, net of portion related to the Company's interest	3,472		3,268
Amounts receivable by the Company	2,415		2,193
Investments in and advances to unconsolidated affiliates, net of Company's share of distributions in excess of income from and investments in unconsolidated affiliates	$	286,778	$	258,337

Schedule of Condensed Income Statement



	Year Ended December 31,
	2017			2016			2015
Combined and Condensed Statements of Income
Total revenues	$	83,222		$	84,218		$	43,990
Operating and other expenses	(24,711		)	(25,724		)	(13,721		)
Interest expense	(18,733		)	(16,300		)	(9,178		)
Equity in earnings of unconsolidated affiliates	—			—			66,655
Depreciation and amortization	(24,192		)	(35,432		)	(12,154		)
Loss on debt extinguishment	(154		)	—			—
Gain (loss) on disposition of properties	18,957			(1,340		)	32,623
Net income attributable to unconsolidated affiliates	$	34,389		$	5,422		$	108,215

Company’s share of equity in net income of unconsolidated affiliates	$	26,039		$	40,538		$	37,722
Basis differential amortization	(2,668		)	(1,089		)	(392		)
Company’s equity in earnings of unconsolidated affiliates	$	23,371		$	39,449		$	37,330

Other Assets, Net and Accounts Payable and Other Liabilities (Tables)

12 Months Ended

Dec. 31, 2017

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Schedule of other assets and other liabilities

Other assets, net and accounts payable and other liabilities are comprised of the following for the periods presented:



	December 31,
(in thousands)	2017			2016
Other assets, net:
Lease intangibles, net (Note 6)	$	127,571		$	114,584
Deferred charges, net ^(a)	24,589			25,221
Prepaid expenses	16,838			14,351
Other receivables	11,356			9,514
Accrued interest receivable	11,668			9,354
Deposits	6,296			4,412
Due from seller	4,300			4,300
Deferred tax assets	2,096			3,733
Derivative financial instruments (Note 8)	4,402			2,921
Due from related parties	1,479			1,655
Corporate assets	2,369			1,241
Income taxes receivable	1,995			1,500
	$	214,959		$	192,786

(a) Deferred charges, net:
Deferred leasing and other costs	$	41,020		$	40,728
Deferred financing costs	7,786			5,915
	48,806			46,643
Accumulated amortization	(24,217		)	(21,422		)
Deferred charges, net	$	24,589		$	25,221

Accounts payable and other liabilities:
Lease intangibles, net (Note 6)	$	104,478		$	105,028
Accounts payable and accrued expenses	61,420			48,290
Deferred income	31,306			35,267
Tenant security deposits, escrow and other	10,029			14,975
Derivative financial instruments (Note 8)	1,467			3,590
Income taxes payable	176			1,287
Other	1,176			235
	$	210,052		$	208,672

Lease Intangibles (Tables)

12 Months Ended

Dec. 31, 2017

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Finite-Lived Intangible Assets

Intangible assets and liabilities are summarized as follows (in thousands):



	December 31, 2017									December 31, 2016
	Gross Carrying Amount			Accumulated Amortization			Net Carrying Amount			Gross Carrying Amount			Accumulated Amortization			Net Carrying Amount
Amortizable Intangible Assets
In-place lease intangible assets	$	193,821		$	(72,749	)	$	121,072		$	156,420		$	(47,827	)	$	108,593
Above-market rent	16,786			(10,287		)	6,499			16,649			(10,658		)	5,991
	$	210,607		$	(83,036	)	$	127,571		$	173,069		$	(58,485	)	$	114,584

Amortizable Intangible Liabilities
Below-market rent	$	(147,232	)	$	43,391		$	(103,841	)	$	(137,032	)	$	32,004		$	(105,028	)
Above-market ground lease	(671		)	34			(637		)	—			—			—
	$	(147,903	)	$	43,425		$	(104,478	)	$	(137,032	)	$	32,004		$	(105,028	)

Schedule of Amortization of Acquired Lease Intangible Assets and Liabilities

The scheduled amortization of acquired lease intangible assets and assumed liabilities as of December 31, 2017 is as follows (in thousands):



Years Ending December 31,	Net Increase in Lease Revenues		Increase to Amortization			Reduction of Rent Expense		Net Income (Expense)
2018	$	10,005	$	(29,005	)	$	58	$	(18,942	)
2019	9,642		(21,678		)	58		(11,978		)
2020	8,655		(16,797		)	58		(8,084		)
2021	7,503		(12,524		)	58		(4,963		)
2022	7,185		(8,778		)	58		(1,535		)
Thereafter	54,352		(32,290		)	347		22,409
Total	$	97,342	$	(121,072	)	$	637	$	(23,093	)

Debt (Tables)

12 Months Ended

Dec. 31, 2017

Debt Disclosure [Abstract]

Schedule of Debt

A summary of the Company’s consolidated indebtedness is as follows (dollars in thousands):



	Interest Rate at December 31,		Maturity Date at	Carrying Value at December 31,
	2017	2016	December 31, 2017	2017			2016
Mortgages Payable
Core Fixed Rate	3.88%-5.89%	3.88%-6.65%	February 2024 - April 2035	$	179,870		$	234,875
Core Variable Rate - Swapped^(a)	1.71%-3.77%	1.71%-3.77%	July 2018 - July 2027	74,152			82,250
Total Core Mortgages Payable				254,022			317,125
Fund II Fixed Rate	1.00%-4.75%	1.00%-5.80%	August 2019 - May 2020	205,262			249,762
Fund II Variable Rate	LIBOR+1.39%	LIBOR+0.62%-LIBOR+2.50%	November 2021	—			142,750
Fund II Variable Rate - Swapped^(a)	2.88%	2.88%	November 2021	19,560			19,779
Total Fund II Mortgages Payable				224,822			412,291
Fund III Variable Rate	Prime+0.50% -LIBOR+4.65%	Prime+0.50%-LIBOR+4.65%	May 2018 - December 2021	65,866			83,467
Fund IV Fixed Rate	3.4%-4.50%	3.4%-4.50%	October 2025-June 2026	10,503			10,503
Fund IV Variable Rate	LIBOR+1.70%-LIBOR+3.95%	LIBOR+1.70%-LIBOR+3.95%	January 2018 - April 2022	250,584			233,139
Fund IV Variable Rate - Swapped^(a)	1.78%	1.78%	May 2019 - April 2022	86,851			14,509
Total Fund IV Mortgages Payable				347,938			258,151
Fund V Variable Rate	LIBOR+2.25%	—	October 2020	28,613			—
Net unamortized debt issuance costs				(12,943		)	(16,642		)
Unamortized premium				856			1,336
Total Mortgages Payable				$	909,174		$	1,055,728
Unsecured Notes Payable
Core Unsecured Term Loans	LIBOR+1.30%-LIBOR+1.60%	LIBOR+1.30%-LIBOR+1.60%	July 2020 - December 2022	$	—		$	51,194
Core Variable Rate Unsecured Term Loans - Swapped^(a)	1.24%-3.77%	1.24%-3.77%	July 2018 - March 2025	300,000			248,806
Total Core Unsecured Notes Payable				300,000			300,000
Fund II Unsecured Notes Payable	LIBOR+1.40%	—	September 2020	31,500			—
Fund IV Term Loan/Subscription Facility	LIBOR+1.65%-LIBOR+2.75%	LIBOR+1.65%-LIBOR+2.75%	December 2018 - October 2019	40,825			134,636
Fund V Subscription Facility	LIBOR+1.60%	—	May 2020	103,300			—
Net unamortized debt issuance costs				(1,890		)	(1,646		)
Total Unsecured Notes Payable				$	473,735		$	432,990
Unsecured Line of Credit
Core Unsecured Line of Credit	LIBOR+1.40%	LIBOR+1.40%	June 2020	$	18,048		$	—
Core Unsecured Line of Credit - Swapped^(a)	1.24%-3.77%	—	July 2018 - March 2025	23,452			—
Total Unsecured Line of Credit				$	41,500		$	—

Total Debt - Fixed Rate ^(b)				$	899,650		$	860,486
Total Debt - Variable Rate ^(c)				538,736			645,185
Total Debt				1,438,386			1,505,671
Net unamortized debt issuance costs				(14,833		)	(18,289		)
Unamortized premium				856			1,336
Total Indebtedness				$	1,424,409		$	1,488,718

__________


(a)	At December 31, 2017, the stated rates ranged from LIBOR + 1.65% to LIBOR +1.90% for Core variable-rate debt; LIBOR + 1.39% for Fund II variable-rate debt; PRIME + 0.50% to LIBOR +4.65% for Fund III variable-rate debt; LIBOR + 1.70% to LIBOR +3.95% for Fund IV variable-rate debt, LIBOR + 2.25% for Fund V and LIBOR + 1.30% to LIBOR +1.60% for Core variable-rate unsecured notes.


(b)	Includes $504,018 and $365,343, respectively, of variable-rate debt that has been fixed with interest rate swap agreements as of the periods presented.


(c)	Includes $141.1 million and $186.6 million, respectively, of variable-rate debt that is subject to interest cap agreements.

Schedule of Maturities of Long-term Debt

The scheduled principal repayments of the Company’s consolidated indebtedness, as of December 31, 2017 are as follows (in thousands):



Year Ending December 31,
2018	$	94,400
2019	213,573
2020	576,379
2021	255,027
2022	98,840
Thereafter	200,167
	1,438,386
Unamortized fair market value of assumed debt	856
Net unamortized debt issuance costs	(14,833		)
Total indebtedness	$	1,424,409

Financial Instruments and Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2017

Fair Value Disclosures [Abstract]

Schedule of fair value, assets and liabilities measured on recurring basis

The following table presents the Company’s fair value hierarchy for those assets and liabilities measured at fair value on a recurring basis (in thousands):



	December 31, 2017						December 31, 2016
	Level 1		Level 2		Level 3		Level 1		Level 2		Level 3
Assets
Money Market Funds	$	3	$	—	$	—	$	20,001	$	—	$	—
Derivative financial instruments	—		4,402		—		—		2,921		—
Liabilities
Derivative financial instruments	—		1,467		—		—		3,590		—

Schedule of derivative financial instruments

The Company had the following interest rate swaps for the periods presented (dollars in thousands):



	Aggregate Notional Amount				Strike Rate			Balance Sheet Location	Fair Value
Derivative Instrument	Aggregate Notional Amount		Effective Date	Maturity Date	Low		High	Balance Sheet Location	December 31, 2017			December 31, 2016
Core
Interest Rate Swaps	$	149,036	Oct 2011 - March 2015	July 2018 - Mar 2025	1.38%	—	3.77%	Other Liabilities	$	(1,438	)	$	(3,218	)
Interest Rate Swaps	248,571		Sep 2012 - July 2017	July 2020 - July 2027	1.24%	—	3.77%	Other Assets	4,076			2,609
	$	397,607							$	2,638		$	(609	)

Fund II
Interest Rate Swap	$	19,560	October 2014	November 2021	2.88%	—	2.88%	Other Liabilities	$	(29	)	$	(228	)
Interest Rate Cap	29,500		April 2013	April 2018	4.00%	—	4.00%	Other Assets	—			—
	$	49,060							$	(29	)	$	(228	)

Fund III
Interest Rate Cap	$	58,000	Dec 2016	Jan 2020	3.00%	—	3.00%	Other Assets	$	14		$	127

Fund IV
Interest Rate Swaps	$	86,851	May 2014 - March 2017	May 2019 - April 2022	1.78%	—	2.11%	Other Assets	$	295		$	—
Interest Rate Swaps	—		May 2014 - March 2017	May 2019 - April 2022	1.78%	—	2.11%	Other Liabilities	—			$	(144	)
Interest Rate Caps	108,900		July 2016 - November 2016	August 2019 - December 2019	3.00%	—	3.00%	Other Assets	17			185
	$	195,751							$	312		$	41

Total asset derivatives									$	4,402		$	2,921
Total liability derivatives									$	(1,467	)	$	(3,590	)

Gain (loss) on derivative instruments within the statement of income

The following table presents the location in the financial statements of the income (losses) recognized related to the Company’s cash flow hedges (in thousands):



	Year Ended December 31,
	2017		2016			2015
Amount of (loss) income related to the effective portion recognized in other comprehensive income	$	634	$	(646	)	$	(5,061	)
Amount of loss related to the effective portion subsequently reclassified to earnings	—		—			—
Amount of gain (loss) related to the ineffective portion and amount excluded from effectiveness testing	—		—			—

Fair value, by balance sheet grouping

The Company’s other financial instruments had the following carrying values and fair values as of the dates shown (dollars in thousands):



		December 31, 2017				December 31, 2016
	Level	Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
Notes Receivable^(a)	3	$	153,829	$	151,712	$	276,163	$	272,052
Mortgage and Other Notes Payable, net^(a)	3	909,174		921,891		1,055,728		1,077,926
Investment in non-traded equity securities ^(b)	3	411		22,824		802		25,194
Unsecured notes payable and Unsecured line of credit, net^(c)	2	515,235		515,330		434,636		435,779

__________

(a)


(b)	Represents Fund II’s cost-method investment in Albertson’s supermarkets (Note 4).

(c)

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income (Tables)

12 Months Ended

Dec. 31, 2017

Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]

Reclassification out of Accumulated Other Comprehensive Income

The following table sets forth the activity in accumulated other comprehensive (loss) income for the year ended December 31, 2017 and 2016 (in thousands):



	Gains or Losses on Derivative Instruments
Balance at January 1, 2017	$	(798	)

Other comprehensive loss before reclassifications	634
Reclassification of realized interest on swap agreements	3,317
Net current period other comprehensive loss	3,951
Net current period other comprehensive loss attributable to noncontrolling interests	(539		)
Balance at December 31, 2017	$	2,614

Balance at January 1, 2016	$	(4,463	)

Other comprehensive loss before reclassifications	(646		)
Reclassification of realized interest on swap agreements	4,576
Net current period other comprehensive loss	3,930
Net current period other comprehensive loss attributable to noncontrolling interests	(265		)
Balance at December 31, 2016	$	(798	)

Change in Noncontrolling Interests

The following table summarizes the change in the noncontrolling interests for the year ended December 31, 2017 and 2016 (dollars in thousands):



	Noncontrolling Interests in Operating Partnership ^(a)			Noncontrolling Interests in Partially-Owned Affiliates ^(b)			Total

Balance at January 1, 2017	$	95,422		$	494,126		$	589,548
Distributions declared of $1.05 per Common OP Unit	(6,453		)	—			(6,453		)
Net income (loss) for the period January 1 through December 31, 2017	4,159			(1,321		)	2,838
Conversion of 5,000 Preferred and 81,453 Common OP Units to Common Shares by limited partners of the Operating Partnership	(1,541		)	—			(1,541		)
Other comprehensive income - unrealized loss on valuation of swap agreements	85			(232		)	(147		)
Reclassification of realized interest expense on swap agreements	141			545			686
Noncontrolling interest contributions	—			85,206			85,206
Noncontrolling interest distributions	—			(32,805		)	(32,805		)
Employee Long-term Incentive Plan Unit Awards	10,457			—			10,457
Rebalancing adjustment ^(d)	651			—			651
Balance at December 31, 2017	$	102,921		$	545,519		$	648,440

Balance at January 1, 2016	$	96,340		$	324,526		$	420,866
Distributions declared of $1.16 per Common OP Unit	(6,753		)	—			(6,753		)
Net income for the period January 1 through December 31, 2016	5,002			56,814			61,816
Conversion of 351,250 Common OP Units to Common Shares by limited partners of the Operating Partnership	(7,892		)	—			(7,892		)
Issuance of Common and Preferred OP Units to acquire real estate	31,429			—			31,429
Acquisition of noncontrolling interests ^(c)	—			(25,925		)	(25,925		)
Other comprehensive income - unrealized loss on valuation of swap agreements	(43		)	(289		)	(332		)
Change in control of previously unconsolidated investment	—			(75,713		)	(75,713		)
Reclassification of realized interest expense on swap agreements	223			374			597
Noncontrolling interest contributions	—			295,108			295,108
Noncontrolling interest distributions	—			(80,769		)	(80,769		)
Employee Long-term Incentive Plan Unit Awards	12,768			—			12,768
Rebalancing adjustment ^(d)	(35,652		)	—			(35,652		)
Balance at December 31, 2016	$	95,422		$	494,126		$	589,548

__________

(a)


(b)	Noncontrolling interests in partially-owned affiliates comprise third-party interests in Funds II, III, IV and V, and Mervyns I and II, and six other subsidiaries.


(c)	During the first quarter of 2016, the Company acquired an additional 8.3% interest in Fund II from a limited partner for $18.4 million, giving the Company an aggregate 28.33% interest. Amount in the table above represents the book value of this transaction.


(d)	Adjustment reflects the difference between the fair value of the consideration received or paid and the book value of the Common Shares, Common OP Units, Preferred OP Units, and LTIP Units involving changes in ownership (the “Rebalancing”).

Leases (Tables)

12 Months Ended

Dec. 31, 2017

Leases [Abstract]

Schedule of Future Minimum Rental Payments for Operating Leases



Year Ending December 31,	Minimum Rental Revenues		Minimum Rental Payments
2018	$	165,893	$	4,540
2019	163,576		4,560
2020	149,453		4,356
2021	130,834		4,302
2022	111,958		4,395
Thereafter	514,271		185,014
Total	$	1,235,985	$	207,167

Segment Reporting (Tables)

12 Months Ended

Dec. 31, 2017

Segment Reporting [Abstract]

Reconciliation of Certain Segment Information from Segments to Consolidated

The following tables set forth certain segment information for the Company (in thousands):



	As of or for the Year Ended December 31, 2017
	Core Portfolio			Funds			Structured Financing		Unallocated			Total
Revenues	$	169,975		$	80,287		$	—	$	—		$	250,262
Depreciation and amortization	(61,705		)	(43,229		)	—		—			(104,934		)
Property operating expenses, other operating and real estate taxes	(45,349		)	(34,449		)	—		—			(79,798		)
Impairment charges	—			(14,455		)	—		—			(14,455		)
General and administrative expenses	—			—			—		(33,756		)	(33,756		)
Operating income	62,921			(11,846		)	—		(33,756		)	17,319
Gain on disposition of properties	—			48,886			—		—			48,886
Interest income	—			—			29,143		—			29,143
Equity in earnings of unconsolidated affiliates inclusive of gains on disposition of properties	3,735			19,636			—		—			23,371
Interest expense	(28,618		)	(30,360		)	—		—			(58,978		)
Gain on change in control	5,571			—			—		—			5,571
Income tax provision	—			—			—		(1,004		)	(1,004		)
Net income	43,609			26,316			29,143		(34,760		)	64,308
Net income attributable to noncontrolling interests	(1,107		)	(1,731		)	—		—			(2,838		)
Net income attributable to Acadia	$	42,502		$	24,585		$	29,143	$	(34,760	)	$	61,470

Real estate at cost	$	2,032,485		$	1,433,997		$	—	$	—		$	3,466,482
Total assets	$	2,305,663		$	1,500,755		$	153,829	$	—		$	3,960,247
Cash paid for acquisition of real estate	$	—		$	200,429		$	—	$	—		$	200,429
Cash paid for development and property improvement costs	$	49,339		$	66,116		$	—	$	—		$	115,455



	As of or for the Year Ended December 31, 2016
	Core Portfolio			Funds			Structured Financing		Unallocated			Total
Revenues	$	150,211		$	39,728		$	—	$	—		$	189,939
Depreciation and amortization	(54,582		)	(15,429		)	—		—			(70,011		)
Property operating expenses, other operating and real estate taxes	(39,598		)	(17,793		)	—		—			(57,391		)
General and administrative expenses	—			—			—		(40,648		)	(40,648		)
Operating income	56,031			6,506			—		(40,648		)	21,889
Gain on disposition of properties	—			81,965			—		—			81,965
Interest income	—			—			25,829		—			25,829
Equity in earnings of unconsolidated affiliates inclusive of gains on disposition of properties	3,774			35,675			—		—			39,449
Interest expense	(27,435		)	(7,210		)	—		—			(34,645		)
Income tax benefit	—			—			—		105			105
Net income	32,370			116,936			25,829		(40,543		)	134,592
Net income attributable to noncontrolling interests	(3,411		)	(58,405		)	—		—			(61,816		)
Net income attributable to Acadia	$	28,959		$	58,531		$	25,829	$	(40,543	)	$	72,776

Real estate at cost	$	1,982,763		$	1,399,237		$	—	$	—		$	3,382,000
Total assets	$	2,271,620		$	1,448,177		$	276,163	$	—		$	3,995,960
Cash paid for acquisition of real estate	$	323,880		$	171,764		$	—	$	—		$	495,644
Cash paid for development and property improvement costs	$	13,434		$	136,000		$	—	$	—		$	149,434



	As of or for the Year Ended December 31, 2015
	Core Portfolio			Funds			Structured Financing		Unallocated			Total
Revenues	$	150,015		$	49,048		$	—	$	—		$	199,063
Depreciation and amortization	(46,223		)	(14,528		)	—		—			(60,751		)
Property operating expenses, other operating and real estate taxes	(37,259		)	(21,223		)	—		—			(58,482		)
Impairment charges	(5,000		)	—			—		—			(5,000		)
General and administrative expenses	—			—			—		(30,368		)	(30,368		)
Operating income	61,533			13,297			—		(30,368		)	44,462
Gain on disposition of properties	—			89,063			—		—			89,063
Interest income	—			—			16,603		—			16,603
Equity in earnings of unconsolidated affiliates inclusive of gains on disposition of properties	1,169			36,161			—		—			37,330
Other	—			—			1,596		—			1,596
Interest expense	(27,945		)	(9,352		)	—		—			(37,297		)
Income tax provision	—			—			—		(1,787		)	(1,787		)
Net income	34,757			129,169			18,199		(32,155		)	149,970
Net income attributable to noncontrolling interests	(140		)	(84,122		)	—		—			(84,262		)
Net income attributable to Acadia	$	34,617		$	45,047		$	18,199	$	(32,155	)	$	65,708

Real estate at cost	$	1,572,681		$	1,163,602		$	—	$	—		$	2,736,283
Total assets	$	1,662,092		$	1,223,039		$	147,188	$	—		$	3,032,319
Cash paid for acquisition of real estate	$	181,884		$	156,816		$	—	$	—		$	338,700
Cash paid for development and property improvement costs	$	16,505		$	147,810		$	—	$	—		$	164,315

Federal Income Taxes (Tables)

12 Months Ended

Dec. 31, 2017

Income Tax Disclosure [Abstract]

Schedule of Reconciliation of Net Income to Taxable Income

Reconciliation of GAAP net income attributable to Acadia to taxable income is as follows:



	Year Ended December 31,
(in thousands)	2017			2016			2015

Net income attributable to Acadia	$	61,470		$	72,776		$	65,708
Deferred cancellation of indebtedness income	2,050			2,050			2,050
Deferred rental and other income ^(a)	(934		)	1,610			82
Book/tax difference - depreciation and amortization ^(a)	21,334			15,189			9,983
Straight-line rent and above- and below-market rent adjustments ^(a)	(10,559		)	(7,882		)	(8,041		)
Book/tax differences - equity-based compensation	5,325			10,307			5,833
Joint venture equity in earnings, net ^(a)	9,114			(2,011		)	5,776
Impairment charges and reserves	—			769			(714		)
Acquisition costs ^(a)	1,135			5,116			1,190
Gains	(5,181		)	—			(760		)
Book/tax differences - miscellaneous	930			(4,924		)	2,573
Taxable income	$	84,684		$	93,000		$	83,680
Distributions declared	$	87,848		$	91,053		$	84,683

__________


(a)	Adjustments from certain subsidiaries and affiliates, which are consolidated for financial reporting but not for tax reporting, are included in the reconciliation item "Joint venture equity in earnings, net."

Schedule of Tax Status of Dividends

The Company has determined that the cash distributed to the shareholders for the periods presented is characterized as follows for Federal income tax purposes:



	Year Ended December 31,
	2017				2016				2015
	Per Share		%		Per Share		%		Per Share		%
Ordinary income	$	0.82	78	%	$	0.77	66	%	$	0.83	68	%
Qualified dividend	—		—	%	—		—	%	—		—	%
Capital gain	0.23		22	%	0.39		34	%	0.39		32	%
Total	$	1.05	100	%	$	1.16	100	%	$	1.22	100	%

Schedule of TRS Income and Provision for Income Taxes



	Year Ended December 31,
	2017			2016			2015
TRS income (loss) before income taxes	$	(3,604	)	$	(1,583	)	$	1,008
(Provision) benefit for income taxes:
Federal	(982		)	378			(526		)
State and local	423			97			(134		)
TRS net income (loss) before noncontrolling interests	(4,163		)	(1,108		)	348
Noncontrolling interests	8			(9		)	(208		)
TRS net income (loss)	$	(4,155	)	$	(1,117	)	$	140

Schedule of Effective Income Tax Rate Reconciliation



	Year Ended December 31,
	2017			2016			2015
Federal tax provision (benefit) at statutory tax rate	$	(1,225	)	$	(538	)	$	343
TRS state and local taxes, net of Federal benefit	(190		)	(84		)	53
Tax effect of:
Permanent differences, net	1,131			1,663			396
Prior year (over) under-accrual, net	(1,541		)	—			938
Effect of Tax Cuts and Jobs Act	1,982			—			—
Other	404			(1,516		)	(131		)
REIT state and local income and franchise taxes	443			370			188
Total provision (benefit) for income taxes	$	1,004		$	(105	)	$	1,787

Earnings Per Common Share (Tables)

12 Months Ended

Dec. 31, 2017

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted



	Year Ended December 31,
(dollars in thousands)	2017			2016			2015
Numerator:
Net income attributable to Acadia	$	61,470		$	72,776		$	65,708
Less: net income attributable to participating securities	(642		)	(793		)	(927		)
Income from continuing operations net of income attributable to participating securities	$	60,828		$	71,983		$	64,781

Denominator:
Weighted average shares for basic earnings per share	83,682,789			76,231,000			68,851,083
Effect of dilutive securities:
Employee unvested restricted shares	2,682			12,550			18,556
Denominator for diluted earnings per share	83,685,471			76,243,550			68,869,639

Basic and diluted earnings per Common Share from continuing operations attributable to Acadia	$	0.73		$	0.94		$	0.94

Anti-Dilutive Shares Excluded from Denominator:
Series A Preferred OP Units	188			188			188
Series A Preferred OP Units - Common share equivalent	25,067			25,067			25,067

Series C Preferred OP Units	136,593			141,593			—
Series C Preferred OP Units - Common share equivalent	479,978			410,207			—

Summary of Quarterly Financial Information (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2017

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Financial Information

The quarterly results of operations of the Company for the years ended December 31, 2017 and 2016 are as follows (in thousands, except per share amounts):



	Three Months Ended ^(a,b,c,d)
	March 31, 2017			June 30, 2017		September 30, 2017			December 31, 2017
Revenues	$	61,999		$	59,504	$	62,678		$	66,081
Net income	19,971			6,108		13,285			24,944
Net (income) loss attributable to noncontrolling interests	(4,340		)	5,952		(418		)	(4,032		)
Net income attributable to Acadia	15,631			12,060		12,867			20,912

Earnings per share attributable to Acadia:
Basic	$	0.18		$	0.14	$	0.15		$	0.25
Diluted	0.18			0.14		0.15			0.25

Weighted average number of shares:
Basic	83,635			83,662		83,700			83,733
Diluted	83,646			83,662		83,700			83,733

Cash dividends declared per Common Share	$	0.26		$	0.26	$	0.26		$	0.27

__________


(a)	The three months ended March 31, 2017 includes the Company’s $2.7 million proportionate share of aggregate gains of $14.5 million on the sales of two unconsolidated properties (Note 4).


(b)	The three months ended June 30, 2017 includes the Company’s $0.8 million proportionate share of a $3.3 million gain on sale of an unconsolidated property (Note 4).


(c)	The three months ended September 30, 2017 includes an aggregate $13.0 million gain on the sales of two consolidated properties (Note 2), of which $10.7 million was attributable to noncontrolling interests as well as an impairment charge of $3.8 million, inclusive of an amount attributable to a noncontrolling interest of $2.7 million (Note 8).


(d)	The three months ended December 31, 2017 includes a $5.6 million gain on change in control of interests (Note 4), an aggregate $35.9 million gain on the sales of three consolidated properties (Note 2), of which $26.7 million was attributable to noncontrolling interests; and an impairment charge of $10.6 million, of which $7.6 million was attributable to noncontrolling interests (Note 8).



	Three Months Ended ^{(a, b, c, d)}
	March 31, 2016			June 30, 2016			September 30, 2016		December 31, 2016
Revenues	$	48,045		$	43,918		$	43,855	$	54,121
Net income	73,875			26,155			326		34,236
Net (income) loss attributable to noncontrolling interests	(44,950		)	(8,237		)	5,786		(14,415		)
Net income attributable to Acadia	28,925			17,918			6,112		19,821
Earnings per share attributable to Acadia:
Basic	$	0.40		$	0.24		$	0.08	$	0.24
Diluted	0.40			0.24			0.08		0.24

Weighted average number of shares:
Basic	70,756			72,896			78,449		82,728
Diluted	71,215			72,896			78,624		82,728

Cash dividends declared per Common Share	$	0.25		$	0.25		$	0.25	$	0.41

__________


(a)	The three months ended March 31, 2016 includes Fund III's $65.4 million gain on sale of its 65% consolidated interest in Cortlandt Town Center of which $49.4 million was attributable to noncontrolling interests (Note 2).


(b)	The three months ended June 30, 2016 includes a $16.6 million gain on sale of Fund III's consolidated Heritage Shops property of which $12.5 million was attributable to noncontrolling interests (Note 2).


(c)	The three months ended June 30, 2016, September 30, 2016 and December 31, 2016 reflect the impact of the de-consolidation of the Company's investment in the Brandywine portfolio, which was effective May 1, 2016 (Note 4).


(d)	The three months ended December 31, 2016 reflect the impact of an out-of-period adjustment resulting in a net decrease to net income of $4.2 million, of which $1.6 million was attributable to noncontrolling interests (Note 1).

Organization, Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017 USD ($) property	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) segment property	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of reportable segments \| segment									3
Rental income									$ 198,941	$ 152,814	$ 158,632
Depreciation and amortization									104,934	70,011	60,751
Interest expense									58,978	34,645	37,297
Equity in earnings (losses) of unconsolidated affiliates									23,371	39,449	37,330
Net income (loss)	$ 24,944	$ 13,285	$ 6,108	$ 19,971	$ 34,236	$ 326	$ 26,155	$ 73,875	64,308	134,592	149,970
Net loss (income) attributable to noncontrolling interests	4,032	$ 418	$ (5,952)	$ 4,340	14,415	$ (5,786)	$ 8,237	$ 44,950	2,838	61,816	84,262
Additional paid-in capital	1,596,514				1,594,926				1,596,514	1,594,926
Noncontrolling interests	648,440				589,548				648,440	589,548
Deferred rent receivables	37,300				34,900				37,300	34,900
Allowance for doubtful accounts receivable	5,900				5,700				5,900	5,700
Adjustment to deferred tax assets									2,000
Lease future payment obligation	207,167								207,167
Capitalized internal leasing costs	$ 1,000				1,100				1,000	1,100	1,400
Net Cash Provided by (Used in) Investing Activities									10,082	(610,970)	(354,503)
Acquisition related costs									2,100	8,200
Net Cash Provided by (Used in) Operating Activities									$ 119,833	$ 111,760	113,598
Buildings
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Property, plant and equipment, useful life									40 years
Building Improvements
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Property, plant and equipment, useful life									15 years
Furniture and fixtures \| Minimum
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Property, plant and equipment, useful life									5 years
Furniture and fixtures \| Maximum
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Property, plant and equipment, useful life									20 years
Operating Partnership, as General Partner or Managing Member
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Equity interest held by Operating Partnership									95.00%	95.00%
Remaining funds rate of distribution to operating partnership (in percent)	20.00%								20.00%
Equity in earnings (losses) of unconsolidated affiliates									$ 23,371	$ 39,449	37,330
Institutional Investors
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Remaining funds rate of distribution to all partners (in percent)	80.00%								80.00%
Restatement Adjustment
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Rental income										(2,100)
Depreciation and amortization										1,700
Interest expense										700
Equity in earnings (losses) of unconsolidated affiliates										200
Net income (loss)					(4,200)					(4,200)
Net loss (income) attributable to noncontrolling interests					(1,600)					(1,600)
Additional paid-in capital					35,700					35,700	31,800
Noncontrolling interests					$ (35,700)					(35,700)	$ (31,800)
Pro Forma \| Accounting Standards Update 2016-15
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Net Cash Provided by (Used in) Investing Activities									$ 6,300	0
Net Cash Provided by (Used in) Operating Activities									$ (6,300)	0
Core Portfolio
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of retail properties \| property	118								118
Properties owned percentage	100.00%								100.00%
Acquisition related costs									$ 1,200	5,500
Opportunity Funds
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of retail properties \| property	58								58
Core Portfolio and Opportunity Funds
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of retail properties \| property	176								176
Acquisition related costs									$ 2,100	$ 8,200

Organization, Basis of Presentation and Summary of Significant Accounting Policies - Schedule of Operating Partnership's Equity Interest (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($)
Fund II and Mervyns II
Variable Interest Entity [Line Items]
Operating Partnership Share of Capital	28.33%
Capital called	$ 347.1
Unfunded Commitment	$ 0.0
Equity Interest Held By Operating Partnership	28.33%
Preferred Return	8.00%
Total distributions	$ 131.6
Fund III
Variable Interest Entity [Line Items]
Operating Partnership Share of Capital	24.54%
Capital called	$ 411.5
Unfunded Commitment	$ 38.5
Equity Interest Held By Operating Partnership	24.54%
Preferred Return	6.00%
Total distributions	$ 551.9
Fund IV
Variable Interest Entity [Line Items]
Operating Partnership Share of Capital	23.12%
Capital called	$ 412.7
Unfunded Commitment	$ 117.3
Equity Interest Held By Operating Partnership	23.12%
Preferred Return	6.00%
Total distributions	$ 131.5
Fund V
Variable Interest Entity [Line Items]
Operating Partnership Share of Capital	20.10%
Capital called	$ 45.8
Unfunded Commitment	$ 474.2
Equity Interest Held By Operating Partnership	20.10%
Preferred Return	6.00%
Total distributions	$ 0.0

Real Estate - Schedule of Real Estate (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Acquisition and Disposition of Properties and Discontinued Operations [Abstract]
Land	$ 658,835	$ 693,252
Buildings and improvements	2,406,488	1,916,288
Tenant improvements	131,850	132,220
Construction in progress	18,642	19,789
Properties under capital lease	76,965	76,965
Total	3,292,780	2,838,514
Less: Accumulated depreciation	(339,862)	(287,066)
Operating real estate, net	2,952,918	2,551,448
Real estate under development	173,702	543,486
Net investments in real estate	$ 3,126,620	$ 3,094,934

Real Estate - Acquisitions and Conversions (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Purchase Price									$ 254,532	$ 756,842
Debt assumed									0	120,672
Acquisition related costs									2,100	8,200
Revenues	$ 66,081	$ 62,678	$ 59,504	$ 61,999	$ 54,121	$ 43,855	$ 43,918	$ 48,045	250,262	189,939	$ 199,063
Net loss	$ 24,944	$ 13,285	$ 6,108	$ 19,971	$ 34,236	$ 326	$ 26,155	$ 73,875	64,308	134,592	149,970
Loss per share (in dollars per share)	$ 0.25	$ 0.15	$ 0.14	$ 0.18	$ 0.24	$ 0.08	$ 0.24	$ 0.40
Purchase Price Allocation
Land	$ 48,138				$ 225,729				48,138	225,729
Buildings and improvements	173,576				458,525				173,576	458,525
Other assets	84				3,481				84	3,481
Acquisition-related intangible assets (in Acquired lease intangibles, net)	44,269				63,606				44,269	63,606
Acquisition-related intangible liabilities (in Acquired lease intangibles, net)	(11,535)				(72,985)				(11,535)	(72,985)
Above and below market debt assumed (included in Mortgages and other notes payable, net)	0				(119,601)				0	(119,601)
Net assets acquired	$ 254,532				$ 558,755				254,532	558,755
Consideration
Cash									200,429	439,546
Conversion of note receivable									41,010	0
Debt assumed									0	120,672
Liabilities assumed									3,363	0
Existing interest in previously unconsolidated investment									4,159	0
Change in control of previously unconsolidated investment									5,571	0	$ 0
Total Consideration									254,532	558,755
2017 Acquisitions
Business Acquisition [Line Items]
Revenues									10,200
Net loss									$ 3,500
Loss per share (in dollars per share)									$ 0.04
2016 Acquisitions
Business Acquisition [Line Items]
Revenues										15,300
Net loss										$ 4,700
Loss per share (in dollars per share)										$ 0.06
Core Portfolio and Opportunity Funds
Business Acquisition [Line Items]
Acquisition related costs									$ 2,100	$ 8,200
Core Portfolio
Business Acquisition [Line Items]
Purchase Price									42,800	519,592
Debt assumed									0	119,209
Acquisition related costs									1,200	5,500
Consideration
Debt assumed									$ 0	$ 119,209
Core Portfolio \| Market Square Shopping Center \| Wilmington, DE
Business Acquisition [Line Items]
Percent Acquired	100.00%								100.00%
Purchase Price									$ 42,800
Debt assumed									0
Consideration
Debt assumed									0
Core Portfolio \| 991 Madison Avenue - New York, NY \| New York, NY
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 76,628
Debt assumed										0
Consideration
Debt assumed										$ 0
Core Portfolio \| 165 Newbury Street - Boston, MA \| Boston, MA
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 6,250
Debt assumed										0
Consideration
Debt assumed										$ 0
Core Portfolio \| Concord & Milwaukee - Chicago, IL \| Chicago, IL
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 6,000
Debt assumed										2,902
Consideration
Debt assumed										$ 2,902
Core Portfolio \| 151 North State Street - Chicago, IL \| Chicago, IL
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 30,500
Debt assumed										14,556
Consideration
Debt assumed										$ 14,556
Core Portfolio \| State & Washington - Chicago, IL \| Chicago, IL
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 70,250
Debt assumed										25,650
Consideration
Debt assumed										$ 25,650
Core Portfolio \| North & Kingsbury - Chicago, IL \| Chicago, IL
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 34,000
Debt assumed										13,409
Consideration
Debt assumed										$ 13,409
Core Portfolio \| Sullivan Center - Chicago, IL \| Chicago, IL
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 146,939
Debt assumed										0
Consideration
Debt assumed										$ 0
Core Portfolio \| California & Armitage - Chicago, IL \| Chicago, IL
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 9,250
Debt assumed										2,692
Consideration
Debt assumed										$ 2,692
Core Portfolio \| 555 9th Street - San Francisco, CA \| San Francisco, CA
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 139,775
Debt assumed										60,000
Consideration
Debt assumed										60,000
Funds Segment
Business Acquisition [Line Items]
Acquisition related costs									900	2,700
Fund IV
Business Acquisition [Line Items]
Purchase Price									44,492	237,250
Debt assumed									0	1,463
Consideration
Debt assumed									$ 0	$ 1,463
Fund IV \| Lincoln Place - Fairview Heights, IL \| Fairview Heights, IL
Business Acquisition [Line Items]
Percent Acquired	100.00%								100.00%
Purchase Price									$ 35,350
Debt assumed									0
Consideration
Debt assumed									$ 0
Fund IV \| Shaw's Plaza Waterville, ME \| Windham, ME
Business Acquisition [Line Items]
Percent Acquired	100.00%								100.00%
Purchase Price									$ 9,142
Debt assumed									0
Consideration
Debt assumed									0
Fund IV \| Shaw's Plaza Waterville, ME \| Waterville, ME
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 13,800
Debt assumed										0
Consideration
Debt assumed										$ 0
Fund IV \| Restaurants at Fort Point - Boston, MA \| Boston, MA
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 11,500
Debt assumed										0
Consideration
Debt assumed										$ 0
Fund IV \| 1964 Union Street San Francisco, CA \| San Francisco, CA
Business Acquisition [Line Items]
Percent Acquired					90.00%					90.00%
Purchase Price										$ 2,250
Debt assumed										1,463
Consideration
Debt assumed										$ 1,463
Fund IV \| Wake Forest Crossing - Wake Forest, NC \| Wake Forest, NC
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 36,600
Debt assumed										0
Consideration
Debt assumed										$ 0
Fund IV \| Airport Mall - Bangor, ME \| Bangor, ME
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 10,250
Debt assumed										0
Consideration
Debt assumed										$ 0
Fund IV \| Colonie Plaza - Albany, NY \| Albany, NY
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 15,000
Debt assumed										0
Consideration
Debt assumed										$ 0
Fund IV \| Dauphin Plaza - Harrisburg, PA \| Harrisburg, PA
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 16,000
Debt assumed										0
Consideration
Debt assumed										$ 0
Fund IV \| JFK Plaza - Waterville, ME \| Waterville, ME
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 6,500
Debt assumed										0
Consideration
Debt assumed										$ 0
Fund IV \| Mayfair Shopping Center - Philadelphia, PA \| Philadelphia, PA
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 16,600
Debt assumed										0
Consideration
Debt assumed										$ 0
Fund IV \| Wells Plaza - Wells, ME \| Wells, ME
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 5,250
Debt assumed										0
Consideration
Debt assumed										$ 0
Fund IV \| 717 N Michigan - Chicago, IL \| Chicago, IL
Business Acquisition [Line Items]
Percent Acquired					100.00%					100.00%
Purchase Price										$ 103,500
Debt assumed										0
Consideration
Debt assumed										$ 0
Fund V
Business Acquisition [Line Items]
Purchase Price									167,240
Debt assumed									0
Consideration
Debt assumed									$ 0
Fund V \| Plaza Santa Fe - Santa Fe, NM \| Santa Fe, NM
Business Acquisition [Line Items]
Percent Acquired	100.00%								100.00%
Purchase Price									$ 35,220
Debt assumed									0
Consideration
Debt assumed									$ 0
Fund V \| Hickory Ridge - Hickory, NC \| Hickory, NC
Business Acquisition [Line Items]
Percent Acquired	100.00%								100.00%
Purchase Price									$ 44,020
Debt assumed									0
Consideration
Debt assumed									$ 0
Fund V \| New Towne Plaza - Canton, MI \| Canton, MI
Business Acquisition [Line Items]
Percent Acquired	100.00%								100.00%
Purchase Price									$ 26,000
Debt assumed									0
Consideration
Debt assumed									$ 0
Fund V \| Fairlane Green \| Allen Park, MI
Business Acquisition [Line Items]
Percent Acquired	100.00%								100.00%
Purchase Price									$ 62,000
Debt assumed									0
Consideration
Debt assumed									$ 0

Real Estate - Dispositions (Details) - Disposal Group, Not Discontinued Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Price	$ 281,338	$ 153,750
Gain/(Loss) on Sale	48,886	81,965
STATEMENTS OF INCOME
Rental revenues	13,021	16,946	$ 31,935
Expenses	(18,964)	(13,653)	(27,265)
Loss on extinguishment of debt	(1,380)	(81)	(111)
(Loss) income from continuing operations of disposed properties before gain on disposition of properties	(7,323)	3,212	4,559
Gain on disposition of properties, net of tax	48,886	81,965	89,063
Net income attributable to noncontrolling interests	(30,072)	(70,850)	(1,732)
Net income attributable to Acadia	11,491	14,327	$ 91,890
Fund III \| New Hyde Park Shopping Center
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Price	22,075
Gain/(Loss) on Sale	6,433
Fund III \| Cortlandt Towne Center
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Price		107,250
Gain/(Loss) on Sale		65,393
Fund III \| Heritage Shops
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Price		46,500
Gain/(Loss) on Sale		$ 16,572
Fund II \| 216th Street
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Price	30,579
Gain/(Loss) on Sale	6,543
Fund II \| City Point Condominium Tower I
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Price	96,000
Gain/(Loss) on Sale	(810)
Fund II \| 260 E 161th Street
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Price	105,684
Gain/(Loss) on Sale	31,537
Fund IV \| 1151 Third Avenue
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Price	27,000
Gain/(Loss) on Sale	$ 5,183

Real Estate - Properties Held For Sale (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2017 USD ($) property	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) property	Dec. 31, 2016 USD ($) property	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Long Lived Assets Held-for-sale [Line Items]
Impairment charges	$ 10,600	$ 3,800	$ 14,455	$ 0	$ 5,000
Mortgage loans on real estate	$ 153,829		$ 153,829	$ 276,163	147,188	$ 102,286
Fund II
Long Lived Assets Held-for-sale [Line Items]
Number of properties held-for-sale \| property	1		1	1
Properties held-for-sale	$ 25,400		$ 25,400	$ 21,500
Mortgage loans on real estate				25,500
Disposal group, held-for-sale
Long Lived Assets Held-for-sale [Line Items]
Impairment charges			10,600
Properties held for sale net loss			$ 12,000	$ 800	$ 0

- Definition

Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

+ References + Details

Real Estate - Pro Forma Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Acquisition and Disposition of Properties and Discontinued Operations [Abstract]
Acquisition related costs	$ 2,100	$ 8,200
Pro forma revenues	266,485	247,843	$ 243,237
Pro forma income from continuing operations	21,878	63,681	52,442
Pro forma net income attributable to Acadia	$ 64,107	$ 82,485	$ 58,232
Pro forma basic and diluted earnings per share (in dollars per share)	$ 0.77	$ 1.02	$ 0.79

Real Estate - Real Estate Under Development and Construction in Progress (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) property	Dec. 31, 2016 property
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense related to building under development demolished, Write-offs	$ 2,000
Number of real estate properties \| property	5	10
Real estate under development, beginning balance	$ 543,486
Transfers In	102,930
Capitalized Costs	32,400
Transfers Out	505,114
Real estate under development, ending balance	$ 173,702
Core Portfolio
Property, Plant and Equipment [Line Items]
Number of real estate properties \| property	2	1
Real estate under development, beginning balance	$ 3,499
Transfers In	22,422
Capitalized Costs	819
Transfers Out	4,843
Real estate under development, ending balance	$ 21,897
Fund Portfolio \| Fund II
Property, Plant and Equipment [Line Items]
Number of real estate properties \| property	0	2
Real estate under development, beginning balance	$ 443,012
Transfers In	0
Capitalized Costs	6,851
Transfers Out	444,955
Real estate under development, ending balance	$ 4,908
Fund Portfolio \| Fund III
Property, Plant and Equipment [Line Items]
Number of real estate properties \| property	2	3
Real estate under development, beginning balance	$ 50,452
Transfers In	0
Capitalized Costs	22,572
Transfers Out	9,085
Real estate under development, ending balance	$ 63,939
Fund Portfolio \| Fund IV
Property, Plant and Equipment [Line Items]
Number of real estate properties \| property	1	4
Real estate under development, beginning balance	$ 46,523
Transfers In	80,508
Capitalized Costs	2,158
Transfers Out	46,231
Real estate under development, ending balance	$ 82,958

Notes Receivable, Net - Schedule of Notes Receivable (Details) $ in Thousands	Dec. 31, 2017 USD ($) debtinstrument	Dec. 31, 2016 USD ($)
Mortgage Loans on Real Estate [Line Items]
Net carrying amount of notes receivable \| $	$ 153,829	$ 276,163
Number of instruments held \| debtinstrument	6
Core Portfolio
Mortgage Loans on Real Estate [Line Items]
Net carrying amount of notes receivable \| $	$ 101,695	216,400
Number of instruments held \| debtinstrument	3
Core Portfolio \| Minimum
Mortgage Loans on Real Estate [Line Items]
Effective interest rate	6.00%
Core Portfolio \| Maximum
Mortgage Loans on Real Estate [Line Items]
Effective interest rate	8.10%
Fund Portfolio \| Fund II
Mortgage Loans on Real Estate [Line Items]
Net carrying amount of notes receivable \| $	$ 31,778	31,007
Number of instruments held \| debtinstrument	1
Effective interest rate	2.50%
Fund Portfolio \| Fund III
Mortgage Loans on Real Estate [Line Items]
Net carrying amount of notes receivable \| $	$ 5,106	4,506
Number of instruments held \| debtinstrument	1
Effective interest rate	18.00%
Fund Portfolio \| Fund IV
Mortgage Loans on Real Estate [Line Items]
Net carrying amount of notes receivable \| $	$ 15,250	$ 24,250
Number of instruments held \| debtinstrument	1
Effective interest rate	15.30%

Notes Receivable, Net - Narrative (Details) $ in Thousands		3 Months Ended		12 Months Ended
Notes Receivable, Net - Narrative (Details) $ in Thousands	May 01, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($) property note_receivable	Dec. 31, 2015 USD ($)
Mortgage Loans on Real Estate [Line Items]
Proceeds from notes receivable				$ 32,000	$ 42,819	$ 15,984
Recovered mortgage amount including accrued interest and fees				16,800
Additional advance				156,344	222,071	$ 90,234
Notes receivable, net				153,829	276,163
Recovered interest income		$ 1,400	$ 2,200
Nonperforming Financial Instruments
Mortgage Loans on Real Estate [Line Items]
Proceeds from notes receivable				12,000
Notes receivable, net					12,000
Notes Receivable \| Collateralized Note, 9.8% Interest Rate
Mortgage Loans on Real Estate [Line Items]
Notes receivable, net					$ 47,500
Effective interest rate					9.80%
Number of properties collateralized \| property					4
Notes Receivable \| Five Notes Issued in Periods Prior to 2016
Mortgage Loans on Real Estate [Line Items]
Proceeds from notes receivable					$ 42,800
Notes receivable, net					$ 29,600
Number of notes repaid \| note_receivable					5
Notes Receivable \| First Mortgage Loan, 8.1% Loan, Due 2019
Mortgage Loans on Real Estate [Line Items]
Effective interest rate					8.10%
Mezzanine Loan \| Mezzanine Loan, 15% Loan
Mortgage Loans on Real Estate [Line Items]
Notes receivable, net					$ 30,900
Effective interest rate					15.00%
Core Portfolio
Mortgage Loans on Real Estate [Line Items]
Notes receivable, net				101,695	$ 216,400
Core Portfolio \| Notes Receivable of $10 million
Mortgage Loans on Real Estate [Line Items]
Additional advance				10,000
Notes receivable, net					$ 20,000
Core Portfolio \| Note Receivable, Due June 1, 2018
Mortgage Loans on Real Estate [Line Items]
Notes receivable, net				$ 15,000
Core Portfolio \| Notes Receivable \| Collateralized Note, 9.8% Interest Rate
Mortgage Loans on Real Estate [Line Items]
Number of receivables issued \| note_receivable					1
Maximum \| Core Portfolio
Mortgage Loans on Real Estate [Line Items]
Effective interest rate				8.10%
Market Square
Mortgage Loans on Real Estate [Line Items]
Notes receivable, net	$ 153,400
Market Square \| Core Portfolio
Mortgage Loans on Real Estate [Line Items]
Note receivable exchanged	$ 92,700
Note receivable accrued interest				$ 1,800
Shopping Center in Windham, ME
Mortgage Loans on Real Estate [Line Items]
Note receivable exchanged				9,000
Note receivable accrued interest				100
Fund III
Mortgage Loans on Real Estate [Line Items]
Additional advance				600
Fund II
Mortgage Loans on Real Estate [Line Items]
Note receivable accrued interest				$ 800
Fund IV \| Notes Receivable \| Collateralized Note, 9.8% Interest Rate
Mortgage Loans on Real Estate [Line Items]
Number of receivables issued \| note_receivable					3

Investments in and Advances to Unconsolidated Affiliates - Schedule of Investments (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage			65.00%
Due from related parties	$ 2,415,000	$ 2,193,000
Other	556,000	957,000
Investments in and advances to unconsolidated affiliates	302,070,000	272,028,000
Distributions in excess of income from, and investments in, unconsolidated affiliates	$ 15,292,000	13,691,000
KLA Mervyns LLC
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	10.50%
Equity method investments	$ 0	0
Fund III Other Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	90.00%
Equity method investments	$ 167,000	8,108,000
Self Storage Management
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	95.00%
Equity method investments	$ 206,000	241,000
Fund III
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 373,000	8,349,000
Broughton St. Portfolio Savannah, GA
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	50.00%
Equity method investments	$ 48,335,000	54,839,000
Cumulative capital contribution, percentage	15.00%
Cumulative capital contribution	$ 15,400,000	14,500,000
Preferred return percentage	9.00%
Preferred return	$ 36,800,000	45,400,000
Fund IV Other Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	90.00%
Equity method investments	$ 20,199,000	21,817,000
650 Bald Hill Road
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	90.00%
Equity method investments	$ 13,609,000	18,842,000
Fund IV
Schedule of Equity Method Investments [Line Items]
Equity method investments	82,143,000	95,498,000
Core Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 216,583,000	165,031,000
Core Portfolio \| 840 N. Michigan
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	88.43%
Equity method investments	$ 69,846,000	74,131,000
Core Portfolio \| Renaissance Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	20.00%
Equity method investments	$ 35,041,000	36,437,000
Core Portfolio \| Gotham Plaza
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	49.00%
Equity method investments	$ 29,416,000	29,421,000
Core Portfolio \| Market Square
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	100.00%
Equity method investments	$ 0	5,469,000
Core Portfolio \| Town Center
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	61.11%
Equity method investments	$ 78,801,000	15,286,000
Core Portfolio \| Georgetown Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	50.00%
Equity method investments	$ 3,479,000	4,287,000
Core Portfolio \| Crossroads
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	49.00%
Distributions in excess of income from, and investments in, unconsolidated affiliates	$ 15,292,000	$ 13,691,000

Investments in and Advances to Unconsolidated Affiliates - Core Portfolio (Details) $ in Thousands				1 Months Ended	3 Months Ended	12 Months Ended
	Nov. 16, 2017 USD ($)	May 01, 2017 USD ($)	Jan. 04, 2017 USD ($) ft²	Apr. 29, 2016 USD ($)	Dec. 31, 2017 USD ($) ft²	Dec. 31, 2017 USD ($) ft² property	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Mar. 31, 2016
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage									65.00%
Purchase Price						$ 254,532	$ 756,842
Notes receivable, net					$ 153,829	153,829	276,163
Gain on change in control and other					5,600	5,571	0	$ 1,596
Core Portfolio
Schedule of Equity Method Investments [Line Items]
Purchase Price						42,800	519,592
Notes receivable, net					101,695	101,695	216,400
Equity method investments					$ 216,583	$ 216,583	165,031
Core Portfolio \| Crossroads
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage					49.00%	49.00%
Square footage of real estate property (in square feet) \| ft²					311,000	311,000
Core Portfolio \| Georgetown Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage					50.00%	50.00%
Square footage of real estate property (in square feet) \| ft²					28,000	28,000
Equity method investments					$ 3,479	$ 3,479	4,287
Core Portfolio \| Gotham Plaza
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage					49.00%	49.00%
Square footage of real estate property (in square feet) \| ft²					123,000	123,000
Percentage of voting interests acquired					49.00%	49.00%
Equity method investments					$ 29,416	$ 29,416	29,421
Core Portfolio \| Renaissance Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage					20.00%	20.00%
Square footage of real estate property (in square feet) \| ft²					213,000	213,000
Percentage of voting interests acquired			20.00%
Number of businesses acquired \| property						18
Equity method investments					$ 35,041	$ 35,041	$ 36,437
Core Portfolio \| Brandywine Portfolio
Schedule of Equity Method Investments [Line Items]
Square footage of real estate property (in square feet) \| ft²					1,000,000	1,000,000
Repayments of debt				$ 140,000
Note receivable exchanged		$ 16,000
Notes receivable, net		153,400			$ 60,700	$ 60,700
Note receivable accrued interest		$ 300
Core Portfolio \| Town Center
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	22.22%				61.11%	61.11%
Equity method investment, ownership percentage by third party	38.89%				38.89%	38.89%
Equity method investments	$ 61,600
Gain on equity method investment	$ 34,500
Core Portfolio \| Market Square
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	22.22%	61.11%
Equity method investment, ownership percentage by third party	38.89%	38.89%
Equity method investments		$ 16,300
Gain on equity method investment		$ 9,800
Core Portfolio \| Chicago, IL
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage					88.43%	88.43%
Square footage of real estate property (in square feet) \| ft²					87,000	87,000
Core Portfolio \| Alexandria, Virginia \| Renaissance Portfolio
Schedule of Equity Method Investments [Line Items]
Square footage of real estate property (in square feet) \| ft²			6,200
Purchase Price			$ 3,000
Number of businesses acquired \| property						2
Core Portfolio \| Washington D.C. \| Renaissance Portfolio
Schedule of Equity Method Investments [Line Items]
Number of businesses acquired \| property						16
Exchange Transaction One \| Core Portfolio \| Brandywine Portfolio
Schedule of Equity Method Investments [Line Items]
Note receivable exchanged	$ 16,000
Note receivable accrued interest	600
Exchange Transaction Two \| Core Portfolio \| Brandywine Portfolio
Schedule of Equity Method Investments [Line Items]
Note receivable exchanged	60,700
Note receivable accrued interest	$ 900

Investments in and Advances to Unconsolidated Affiliates - Fund Investments (Details)					1 Months Ended	3 Months Ended					12 Months Ended
	Jun. 30, 2017 USD ($)	Feb. 15, 2017 USD ($)	Dec. 21, 2016 USD ($)	Jan. 28, 2016 USD ($)	Jan. 31, 2017 USD ($)	Dec. 31, 2017 USD ($) property properties	Dec. 21, 2017 USD ($) properties	Sep. 30, 2017 USD ($) property	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($) property	Dec. 31, 2017 USD ($) property properties	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Jan. 31, 2018 properties
Schedule of Equity Method Investments [Line Items]
Cost method investments						$ 556,000					$ 556,000	$ 957,000
Equity in earnings (losses) of unconsolidated affiliates											23,371,000	39,449,000	$ 37,330,000
Mervyns I and Mervyns II
Schedule of Equity Method Investments [Line Items]
Distribution from equity method investment											1,100,000
Equity method investments						0					0
Albertson's
Schedule of Equity Method Investments [Line Items]
Distribution from cost method investment											2,400,000
Cost method investments						0					0
Equity in earnings (losses) of unconsolidated affiliates											2,000,000
Fund IV
Schedule of Equity Method Investments [Line Items]
Equity method investments						82,143,000					82,143,000	95,498,000
Fund III
Schedule of Equity Method Investments [Line Items]
Equity method investments						$ 373,000					$ 373,000	$ 8,349,000
Broughton St. Portfolio Savannah, GA \| Fund IV
Schedule of Equity Method Investments [Line Items]
Number of retail properties \| properties						18					18
Disposed of by sale
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal						$ 35,900,000		$ 13,000,000	$ 3,300,000	$ 14,500,000
Number of retail properties \| property						3		2		2	3
Disposed of by sale \| Cortlandt Towne Center
Schedule of Equity Method Investments [Line Items]
Consideration received			$ 57,800,000	$ 107,300,000
Proceeds from sale of equity method investments			25,200,000
Gain (loss) on disposal			$ 36,000,000	$ 65,400,000
Percentage of disposition			35.00%	65.00%
Disposed of by sale \| Cortlandt Towne Center \| Mortgages
Schedule of Equity Method Investments [Line Items]
Repayments of debt			$ 32,600,000
Disposed of by sale \| Partnership Interest
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal									800,000	$ 2,700,000
Disposed of by sale \| Partnership Interest \| Cortlandt Towne Center
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal			$ 8,800,000
Disposed of by sale \| 2819 Kennedy Boulevard \| Fund IV
Schedule of Equity Method Investments [Line Items]
Consideration received					$ 19,000,000
Proceeds from sale of equity method investments					10,600,000
Gain (loss) on disposal					6,300,000
Disposed of by sale \| 2819 Kennedy Boulevard \| Fund IV \| Mortgages
Schedule of Equity Method Investments [Line Items]
Repayments of debt					8,400,000
Disposed of by sale \| 2819 Kennedy Boulevard \| Affiliated Entity \| Fund IV
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal					6,200,000
Disposed of by sale \| 2819 Kennedy Boulevard \| Partnership Interest \| Fund IV
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal					$ 1,400,000
Disposed of by sale \| Arundel Plaza \| Fund III
Schedule of Equity Method Investments [Line Items]
Consideration received		$ 28,800,000
Proceeds from sale of equity method investments		18,800,000
Gain (loss) on disposal		8,200,000
Disposed of by sale \| Arundel Plaza \| Fund III \| Mortgages
Schedule of Equity Method Investments [Line Items]
Repayments of debt		10,000,000
Disposed of by sale \| Arundel Plaza \| Affiliated Entity \| Fund III
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal		5,300,000
Disposed of by sale \| Arundel Plaza \| Partnership Interest \| Fund III
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal		$ 1,300,000
Disposed of by sale \| 1701 Belmont Avenue \| Fund IV
Schedule of Equity Method Investments [Line Items]
Consideration received	$ 5,600,000								$ 5,600,000
Proceeds from sale of equity method investments	2,700,000
Disposed of by sale \| 1701 Belmont Avenue \| Fund IV \| Mortgages
Schedule of Equity Method Investments [Line Items]
Repayments of debt	2,900,000
Disposed of by sale \| 1701 Belmont Avenue \| Affiliated Entity \| Fund IV
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal	$ 3,300,000
Disposed of by sale \| Broughton St. Portfolio Savannah, GA \| Fund IV
Schedule of Equity Method Investments [Line Items]
Proceeds from sale of equity method investments							$ 11,000,000
Gain (loss) on disposal							$ 1,200,000
Number of retail properties \| properties							5
Disposed of by sale \| Broughton St. Portfolio Savannah, GA \| Affiliated Entity \| Fund IV
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal							$ 600,000
Disposed of by sale \| Broughton St. Portfolio Savannah, GA \| Partnership Interest \| Fund IV
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal							$ 100,000
Subsequent Event \| Disposed of by sale \| Broughton St. Portfolio Savannah, GA \| Fund IV
Schedule of Equity Method Investments [Line Items]
Number of retail properties \| properties														2

Investments in and Advances to Unconsolidated Affiliates - Unconsolidated Affiliates (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Combined and Condensed Balance Sheets
Real estate under development	$ 173,702				$ 543,486				$ 173,702	$ 543,486
Investments in and advances to unconsolidated affiliates	302,070				272,028				302,070	272,028
Other assets	214,959				192,786				214,959	192,786
Total assets	3,960,247				3,995,960				3,960,247	3,995,960
Total liabilities and equity	3,960,247				3,995,960				3,960,247	3,995,960
Investments in and advances to unconsolidated affiliates, net of Company's share of distributions in excess of income from and investments in unconsolidated affiliates	286,778				258,337				286,778	258,337
Combined and Condensed Statements of Income
Total revenues	66,081	$ 62,678	$ 59,504	$ 61,999	54,121	$ 43,855	$ 43,918	$ 48,045	250,262	189,939	$ 199,063
Operating and other expenses									(232,943)	(168,050)	(154,601)
Depreciation and amortization									(104,934)	(70,011)	(60,751)
Income from continuing operations before gain on disposition of properties									15,422	52,627	60,907
Company’s equity in earnings of unconsolidated affiliates									23,371	39,449	37,330
Equity Method Investee
Schedule of Equity Method Investments [Line Items]
Related party revenue									1,300	1,200	300
Expenses, related party									2,000	2,400	2,500
Unconsolidated Affiliates
Combined and Condensed Balance Sheets
Rental property, net	518,900				576,505				518,900	576,505
Real estate under development	26,681				18,884				26,681	18,884
Investments in and advances to unconsolidated affiliates	6,853				6,853				6,853	6,853
Other assets	100,901				75,254				100,901	75,254
Total assets	653,335				677,496				653,335	677,496
Mortgage notes payable	405,652				407,344				405,652	407,344
Other liabilities	61,932				30,117				61,932	30,117
Partners’ equity	185,751				240,035				185,751	240,035
Total liabilities and equity	653,335				677,496				653,335	677,496
Company's share of accumulated equity	185,533				191,049				185,533	191,049
Basis differential	95,358				61,827				95,358	61,827
Deferred fees, net of portion related to the Company's interest	3,472				3,268				3,472	3,268
Amounts receivable by the Company	$ 2,415				$ 2,193				2,415	2,193
Combined and Condensed Statements of Income
Total revenues									83,222	84,218	43,990
Operating and other expenses									(24,711)	(25,724)	(13,721)
Interest expense									(18,733)	(16,300)	(9,178)
Depreciation and amortization									(24,192)	(35,432)	(12,154)
Loss on debt extinguishment									(154)	0	0
Gain (loss) on disposition of properties									18,957	(1,340)	32,623
Income from continuing operations before gain on disposition of properties									34,389	5,422	108,215
Company’s equity in earnings of unconsolidated affiliates									0	0	66,655
Operating Partnership, as General Partner or Managing Member
Combined and Condensed Statements of Income
Company’s share of equity in net income of unconsolidated affiliates									26,039	40,538	37,722
Basis differential amortization									(2,668)	(1,089)	(392)
Company’s equity in earnings of unconsolidated affiliates									$ 23,371	$ 39,449	$ 37,330

Other Assets, Net and Accounts Payable and Other Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Other assets, net:
Lease intangibles, net (Note 6)	$ 127,571	$ 114,584
Deferred charges, net	24,589	25,221
Prepaid expenses	16,838	14,351
Other receivables	11,356	9,514
Accrued interest receivable	11,668	9,354
Deposits	6,296	4,412
Due from seller	4,300	4,300
Deferred tax assets	2,096	3,733
Derivative financial instruments (Note 8)	4,402	2,921
Due from related parties	1,479	1,655
Corporate assets	2,369	1,241
Income taxes receivable	1,995	1,500
Other assets, net	214,959	192,786
Deferred charges, net:
Deferred leasing and other costs	41,020	40,728
Deferred financing costs	7,786	5,915
Deferred costs, gross	48,806	46,643
Accumulated amortization	(24,217)	(21,422)
Deferred charges, net	24,589	25,221
Accounts payable and other liabilities:
Lease intangibles, net (Note 6)	104,478	105,028
Accounts payable and accrued expenses	61,420	48,290
Deferred income	31,306	35,267
Tenant security deposits, escrow and other	10,029	14,975
Derivative financial instruments (Note 8)	1,467	3,590
Income taxes payable	176	1,287
Other	1,176	235
Accounts payable and other liabilities	$ 210,052	$ 208,672

Lease Intangibles - Schedule of Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Amortizable Intangible Assets, Gross Carrying Amount	$ 210,607	$ 173,069
Amortizable Intangible Assets, Accumulated Amortization	(83,036)	(58,485)
Amortizable Intangible Assets, Net Carrying Amount	127,571	114,584
Amortizable Intangible Liabilities
Amortizable Intangible Liabilities, Gross Carrying Amount	(147,232)	(137,032)
Amortizable Intangible Liabilities, Accumulated Amortization	43,391	32,004
Amortizable Intangible Liabilities, Net Carrying Amount	(103,841)	(105,028)
Above-market Ground Lease, Gross	(671)	0
Above-market Ground Lease, Accumulated Amortization	34	0
Above-market Ground Lease, Net	(637)	0
Finite-Lived Intangible Liabilities, Gross	(147,903)	(137,032)
Finite-Lived Intangible Liabilities, Accumulated Amortization	43,425	32,004
Finite-Lived Intangible Liabilities, Net	(104,478)	(105,028)
Below market rents, acquired	$ 10,900
Below market rents acquired, weighted average useful life	12 years 1 month
Above-market ground lease, acquired	$ 700
Above-market ground lease acquired, weighted average useful life	11 years 6 months
In-place lease intangible assets
Finite-Lived Intangible Assets [Line Items]
Amortizable Intangible Assets, Gross Carrying Amount	$ 193,821	156,420
Amortizable Intangible Assets, Accumulated Amortization	(72,749)	(47,827)
Amortizable Intangible Assets, Net Carrying Amount	121,072	108,593
Intangible assets acquired	$ 41,600
Acquired intangible assets, weighted average useful life	4 years 1 month
Above-market rent
Finite-Lived Intangible Assets [Line Items]
Amortizable Intangible Assets, Gross Carrying Amount	$ 16,786	16,649
Amortizable Intangible Assets, Accumulated Amortization	(10,287)	(10,658)
Amortizable Intangible Assets, Net Carrying Amount	6,499	$ 5,991
Intangible assets acquired	$ 2,700
Acquired intangible assets, weighted average useful life	4 years 9 months

Lease Intangibles - Scheduled Amortization (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Acquired Lease Intangibles [Abstract]
Amortizable Intangible Assets, Net Carrying Amount	$ (127,571)	$ (114,584)
In-place lease intangible assets
Acquired Lease Intangibles [Abstract]
2018, Net Increase In Lease Revenues	10,005
2019, Net Increase In Lease Revenues	9,642
2020, Net Increase In Lease Revenues	8,655
2021, Net Increase In Lease Revenues	7,503
2022, Net Increase In Lease Revenues	7,185
Thereafter, Net Increase In Lease Revenues	54,352
Net Increase In Lease Revenues, Total	97,342
2018, Increase to Amortization	(29,005)
2019, Increase to Amortization	(21,678)
2020, Increase to Amortization	(16,797)
2021, Increase to Amortization	(12,524)
2022, Increase to Amortization	(8,778)
Thereafter, Increase to Amortization	(32,290)
Amortizable Intangible Assets, Net Carrying Amount	(121,072)	$ (108,593)
2018, Reduction of Rent Expense	58
2019, Reduction of Rent Expense	58
2020, Reduction of Rent Expense	58
2021, Reduction of Rent Expense	58
2022, Reduction of Rent Expense	58
Thereafter, Reduction of Rent Expense	347
Reduction of Rent Expense, Total	637
2018, Net Income (Expense)	(18,942)
2019, Net Income (Expense)	(11,978)
2020, Net Income (Expense)	(8,084)
2021, Net Income (Expense)	(4,963)
2022, Net Income (Expense)	(1,535)
Thereafter, Net Income (Expense)	22,409
Total, Net Income (Expense)	$ (23,093)

Debt - Summary of Consolidated Indebtedness (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term debt, gross	$ 1,438,386	$ 1,505,671
Mortgage and other notes payable, net	909,174	1,055,728
Unsecured notes payable, net	473,735	432,990
Unsecured line of credit	41,500	0
Net unamortized debt issuance costs	(14,833)	(18,289)
Unamortized fair market value of assumed debt	856	1,336
Total indebtedness	1,424,409	1,488,718
Letters of credit, outstanding amount	19,700	11,300
Total Debt - Fixed and Effectively Fixed Rate
Debt Instrument [Line Items]
Long-term debt, gross	899,650	860,486
Total Debt - Variable Rate
Debt Instrument [Line Items]
Long-term debt, gross	538,736	645,185
Total Debt - Variable Rate Fixed and Effectively Fixed Rate During Period
Debt Instrument [Line Items]
Long-term debt, gross	504,018	365,343
Variable-rate debt that subject to interest cap agreements
Debt Instrument [Line Items]
Long-term debt, gross	141,100	186,600
Mortgages
Debt Instrument [Line Items]
Mortgage and other notes payable, net	909,174	1,055,728
Net unamortized debt issuance costs	(12,943)	(16,642)
Unamortized fair market value of assumed debt	$ 856	1,336
Mortgages \| LIBOR
Debt Instrument [Line Items]
Interest rate, stated percentage	3.90%
Unsecured Debt
Debt Instrument [Line Items]
Unsecured notes payable, net	$ 473,735	432,990
Net unamortized debt issuance costs	(1,890)	(1,646)
Line of Credit
Debt Instrument [Line Items]
Unsecured line of credit	$ 41,500	0
Core Portfolio \| Variable Rate Debt \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.65%
Core Portfolio \| Variable Rate Debt \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	1.90%
Core Portfolio \| Variable Rate Unsecured Term Loans - Swapped \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.30%
Core Portfolio \| Variable Rate Unsecured Term Loans - Swapped \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	1.60%
Core Portfolio \| Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	$ 254,022	317,125
Core Portfolio \| Mortgages \| Fixed Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 179,870	$ 234,875
Core Portfolio \| Mortgages \| Fixed Rate \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	3.88%	3.88%
Core Portfolio \| Mortgages \| Fixed Rate \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	5.89%	5.89%
Core Portfolio \| Mortgages \| Variable Rate - Swapped
Debt Instrument [Line Items]
Long-term debt, gross	$ 74,152	$ 82,250
Core Portfolio \| Mortgages \| Variable Rate - Swapped \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	1.71%	1.71%
Core Portfolio \| Mortgages \| Variable Rate - Swapped \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	3.77%	3.77%
Core Portfolio \| Unsecured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 300,000	$ 300,000
Core Portfolio \| Unsecured Debt \| Unsecured Term Loans
Debt Instrument [Line Items]
Long-term debt, gross	$ 0	$ 51,194
Core Portfolio \| Unsecured Debt \| Unsecured Term Loans \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.30%	1.30%
Core Portfolio \| Unsecured Debt \| Unsecured Term Loans \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	1.60%	1.60%
Core Portfolio \| Unsecured Debt \| Variable Rate Unsecured Term Loans - Swapped
Debt Instrument [Line Items]
Long-term debt, gross	$ 300,000	$ 248,806
Core Portfolio \| Unsecured Debt \| Variable Rate Unsecured Term Loans - Swapped \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	1.24%	1.24%
Core Portfolio \| Unsecured Debt \| Variable Rate Unsecured Term Loans - Swapped \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	3.77%	3.77%
Core Portfolio \| Line of Credit \| Unsecured Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross	$ 18,048	$ 0
Core Portfolio \| Line of Credit \| Unsecured Line of Credit \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.40%	1.40%
Core Portfolio \| Line of Credit \| Unsecured Line of Credit - Swapped
Debt Instrument [Line Items]
Long-term debt, gross	$ 23,452	$ 0
Core Portfolio \| Line of Credit \| Unsecured Line of Credit - Swapped \| LIBOR \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	1.24%
Core Portfolio \| Line of Credit \| Unsecured Line of Credit - Swapped \| LIBOR \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	3.77%
Fund II \| Fund Portfolio \| Variable Rate Debt \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.39%
Fund II \| Fund Portfolio \| Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	$ 224,822	412,291
Fund II \| Fund Portfolio \| Mortgages \| Fixed Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 205,262	$ 249,762
Fund II \| Fund Portfolio \| Mortgages \| Fixed Rate \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	1.00%	1.00%
Fund II \| Fund Portfolio \| Mortgages \| Fixed Rate \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	4.75%	5.80%
Fund II \| Fund Portfolio \| Mortgages \| Variable Rate - Swapped
Debt Instrument [Line Items]
Interest rate, stated percentage	2.88%	2.88%
Long-term debt, gross	$ 19,560	$ 19,779
Fund II \| Fund Portfolio \| Mortgages \| Variable Rate Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 0	$ 142,750
Fund II \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.39%
Fund II \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate		0.62%
Fund II \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate		2.50%
Fund II \| Fund Portfolio \| Unsecured Debt \| Unsecured Notes Payable
Debt Instrument [Line Items]
Long-term debt, gross	$ 31,500	$ 0
Fund II \| Fund Portfolio \| Unsecured Debt \| Unsecured Notes Payable \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.40%
Fund III \| Fund Portfolio \| Variable Rate Debt \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	4.65%
Fund III \| Fund Portfolio \| Variable Rate Debt \| Prime Rate \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Fund III \| Fund Portfolio \| Mortgages \| Variable Rate Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 65,866	$ 83,467
Fund III \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	4.65%	4.65%
Fund III \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| Prime Rate \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%	0.50%
Fund IV \| Fund Portfolio \| Variable Rate Debt \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.70%
Fund IV \| Fund Portfolio \| Variable Rate Debt \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	3.95%
Fund IV \| Fund Portfolio \| Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	$ 347,938	$ 258,151
Fund IV \| Fund Portfolio \| Mortgages \| Fixed Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 10,503	$ 10,503
Fund IV \| Fund Portfolio \| Mortgages \| Fixed Rate \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	3.40%	3.40%
Fund IV \| Fund Portfolio \| Mortgages \| Fixed Rate \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	4.50%	4.50%
Fund IV \| Fund Portfolio \| Mortgages \| Variable Rate - Swapped
Debt Instrument [Line Items]
Interest rate, stated percentage	1.78%	1.78%
Long-term debt, gross	$ 86,851	$ 14,509
Fund IV \| Fund Portfolio \| Mortgages \| Variable Rate Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 250,584	$ 233,139
Fund IV \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.70%	1.70%
Fund IV \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	3.95%	3.95%
Fund IV \| Fund Portfolio \| Unsecured Debt \| Term Loan / Subscription Facility
Debt Instrument [Line Items]
Long-term debt, gross	$ 40,825	$ 134,636
Fund IV \| Fund Portfolio \| Unsecured Debt \| Term Loan / Subscription Facility \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.65%	1.65%
Fund IV \| Fund Portfolio \| Unsecured Debt \| Term Loan / Subscription Facility \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	2.75%	2.75%
Fund V \| Unsecured Debt \| Subscription Line \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.60%
Fund V \| Fund Portfolio \| Mortgages \| Variable Rate Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 28,613	$ 0
Fund V \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Fund V \| Fund Portfolio \| Unsecured Debt \| Subscription Line
Debt Instrument [Line Items]
Long-term debt, gross	$ 103,300	$ 0
Fund V \| Fund Portfolio \| Unsecured Debt \| Subscription Line \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.60%	1.60%
Revolving Credit Facility \| Core Portfolio \| Unsecured Debt
Debt Instrument [Line Items]
Letters of credit, outstanding amount	$ 12,300	$ 11,300

Debt - Mortgage Payable (Details)	12 Months Ended
Debt - Mortgage Payable (Details)	Dec. 31, 2017 USD ($) property derivative loan	Dec. 31, 2016 USD ($) property
Debt Instrument [Line Items]
Number of interest rate derivatives held \| derivative	8
Mortgages
Debt Instrument [Line Items]
Number of mortgage loans \| loan	11
Borrowings, amount	$ 162,900,000.0
Number of properties collateralized \| property	42	39
Number of notes repaid \| loan	13
Repayments of debt	$ 280,800,000
Annual principal payment	1,000,000
Interest Rate Swaps \| Mortgages
Debt Instrument [Line Items]
Derivative, notional amount	$ 73,300,000
Weighted average interest rate	2.11%
Core Portfolio
Debt Instrument [Line Items]
Derivative, notional amount	$ 397,607,000
Brandywine Portfolio \| Core Portfolio \| Mortgages
Debt Instrument [Line Items]
Interest rate, stated percentage	5.99%
Debt default, amount	$ 26,300,000	$ 26,300,000
Debt default interest	5.00%
Interest owner percentage in property	22.00%
Lawsuit damages sought, value	$ 32,100,000
LIBOR \| Mortgages
Debt Instrument [Line Items]
Basis spread on variable rate	3.47%
Interest rate, stated percentage	3.90%

Debt - Unsecured Notes Payable (Details)	12 Months Ended
Debt - Unsecured Notes Payable (Details)	Dec. 31, 2017 USD ($) debtinstrument	Dec. 31, 2016 USD ($)
Debt Instrument [Line Items]
Number of instruments held \| debtinstrument	6
Letters of credit, outstanding amount	$ 19,700,000	$ 11,300,000
Unsecured Notes Payable \| Unsecured Debt
Debt Instrument [Line Items]
Debt available balance	70,300,000	9,900,000
Fund IV \| Letter of Credit \| Unsecured Debt
Debt Instrument [Line Items]
Letters of credit, outstanding amount	7,400,000	0
Fund IV \| Bridge facility \| Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity	41,812,000
Long-term line of credit, noncurrent	40,800,000	40,100,000
Remaining borrowing capacity	1,000,000	0
Fund IV \| Subscription Line \| Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity	21,500,000.0
Long-term line of credit, noncurrent	0	94,500,000
Remaining borrowing capacity	14,100,000	$ 5,500,000
Fund V \| Subscription Line \| Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity	150,000,000.0
Long-term line of credit, noncurrent	103,300,000
Remaining borrowing capacity	46,700,000
Fund II \| Term Loan Maturing In September 2020 \| Secured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity	40,000,000.0
Long-term line of credit, noncurrent	31,500,000
Remaining borrowing capacity	$ 8,500,000
LIBOR \| Fund V \| Subscription Line \| Unsecured Debt
Debt Instrument [Line Items]
Basis spread on variable rate	1.60%
LIBOR \| Fund II \| Term Loan Maturing In September 2020 \| Secured Debt
Debt Instrument [Line Items]
Basis spread on variable rate	1.40%
Core Portfolio
Debt Instrument [Line Items]
Number of instruments held \| debtinstrument	3
Core Portfolio \| $300 Million Term Loan \| Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 300,000,000.0
Core Portfolio \| $150 Million Term Loan \| Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity	150,000,000.0
Core Portfolio \| $50 Million Term Loan \| Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 50,000,000.0
Number of instruments held	3

Debt - Unsecured Lines of Credit (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Letters of credit, outstanding amount	$ 19,700,000	$ 11,300,000
Core Portfolio \| Revolving Credit Facility \| Unsecured Debt
Debt Instrument [Line Items]
Debt available balance	96,200,000	138,700,000
Maximum borrowing capacity	150,000,000.0
Credit facility amount outstanding	41,500,000	0
Letters of credit, outstanding amount	$ 12,300,000	$ 11,300,000

Debt - Scheduled Principal Repayments (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Debt Disclosure [Abstract]
2018	$ 94,400
2019	213,573
2020	576,379
2021	255,027
2022	98,840
Thereafter	200,167
Long-term debt and convertible notes payable	1,438,386	$ 1,505,671
Unamortized fair market value of assumed debt	856	1,336
Net unamortized debt issuance costs	(14,833)	(18,289)
Total indebtedness	$ 1,424,409	$ 1,488,718

Financial Instruments and Fair Value Measurements - Schedule of Assets and Liabilities on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Assets
Derivative financial instruments	$ 4,402	$ 2,921
Liabilities
Derivative financial instruments	1,467	3,590
Recurring \| Level 1
Assets
Money Market Funds	3	20,001
Derivative financial instruments	0	0
Liabilities
Derivative financial instruments	0	0
Recurring \| Level 2
Assets
Money Market Funds	0	0
Recurring \| Level 3
Assets
Money Market Funds	0	0
Derivative financial instruments	0	0
Liabilities
Derivative financial instruments	$ 0	$ 0

Financial Instruments and Fair Value Measurements - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charges	$ 10,600	$ 3,800	$ 14,455	$ 0	$ 5,000
Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Borrowings, amount					26,300
Disposal group, held-for-sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charges			$ 10,600
Disposal group, held-for-sale \| Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charges					5,000
Noncontrolling Interests
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charges	$ 7,600	$ 2,700
Noncontrolling Interests \| Disposal group, held-for-sale \| Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment charges					$ 1,100

Financial Instruments and Fair Value Measurements - Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Fair value, liability derivatives	$ (1,467)	$ (3,590)
Fair value, asset derivatives	4,402	2,921
Core Portfolio
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	397,607
Fair value, derivatives, net	2,638	(609)
Core Portfolio \| Interest Rate Swaps \| Other Liabilities
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	149,036
Fair value, liability derivatives	$ (1,438)	(3,218)
Core Portfolio \| Interest Rate Swaps \| Other Liabilities \| Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	1.38%
Core Portfolio \| Interest Rate Swaps \| Other Liabilities \| Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	3.77%
Core Portfolio \| Interest Rate Swaps \| Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 248,571
Fair value, asset derivatives	$ 4,076	2,609
Core Portfolio \| Interest Rate Swaps \| Other Assets \| Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	1.24%
Core Portfolio \| Interest Rate Swaps \| Other Assets \| Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	3.77%
Fund Portfolio \| Fund II
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 49,060
Fair value, derivatives, net	(29)	(228)
Fund Portfolio \| Fund II \| Interest Rate Swaps \| Other Liabilities
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	19,560
Fair value, liability derivatives	$ (29)	(228)
Fund Portfolio \| Fund II \| Interest Rate Swaps \| Other Liabilities \| Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	2.88%
Fund Portfolio \| Fund II \| Interest Rate Swaps \| Other Liabilities \| Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	2.88%
Fund Portfolio \| Fund II \| Interest Rate Cap \| Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 29,500
Fair value, asset derivatives	$ 0	0
Fund Portfolio \| Fund II \| Interest Rate Cap \| Other Assets \| Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	4.00%
Fund Portfolio \| Fund II \| Interest Rate Cap \| Other Assets \| Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	4.00%
Fund Portfolio \| Fund III \| Interest Rate Cap \| Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 58,000
Fair value, asset derivatives	$ 14	127
Fund Portfolio \| Fund III \| Interest Rate Cap \| Other Assets \| Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	3.00%
Fund Portfolio \| Fund III \| Interest Rate Cap \| Other Assets \| Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	3.00%
Fund Portfolio \| Fund IV
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 195,751
Fair value, derivatives, net	312	41
Fund Portfolio \| Fund IV \| Interest Rate Swaps \| Other Liabilities
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	0
Fair value, liability derivatives	$ 0	(144)
Fund Portfolio \| Fund IV \| Interest Rate Swaps \| Other Liabilities \| Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	1.78%
Fund Portfolio \| Fund IV \| Interest Rate Swaps \| Other Liabilities \| Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	2.11%
Fund Portfolio \| Fund IV \| Interest Rate Swaps \| Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 86,851
Fair value, liability derivatives	$ 295	0
Fund Portfolio \| Fund IV \| Interest Rate Swaps \| Other Assets \| Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	1.78%
Fund Portfolio \| Fund IV \| Interest Rate Swaps \| Other Assets \| Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	2.11%
Fund Portfolio \| Fund IV \| Interest Rate Cap \| Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 108,900
Fair value, asset derivatives	$ 17	$ 185
Fund Portfolio \| Fund IV \| Interest Rate Cap \| Other Assets \| Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	3.00%
Fund Portfolio \| Fund IV \| Interest Rate Cap \| Other Assets \| Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	3.00%

Financial Instruments and Fair Value Measurements - Gain (Loss) from Derivative Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (loss) income related to the effective portion recognized in other comprehensive income			$ (5,061)
Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (loss) income related to the effective portion recognized in other comprehensive income	$ 634	$ (646)
Amount of loss related to the effective portion subsequently reclassified to earnings	0	0	0
Amount of gain (loss) related to the ineffective portion and amount excluded from effectiveness testing	$ 0	$ 0	$ 0

Financial Instruments and Fair Value Measurements - Fair Value by Balance Sheet Grouping (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, net	$ 153,829	$ 276,163
Mortgage and Other Notes Payable, net	1,424,409	1,488,718
Unsecured notes payable and Unsecured line of credit, net	473,735	432,990
Carrying Amount \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, net	153,829	276,163
Mortgage and Other Notes Payable, net	909,174	1,055,728
Investment in non-traded equity securities	411	802
Carrying Amount \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unsecured notes payable and Unsecured line of credit, net	515,235	434,636
Estimated Fair Value \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes receivable, net	151,712	272,052
Mortgage and Other Notes Payable, net	921,891	1,077,926
Investment in non-traded equity securities	22,824	25,194
Estimated Fair Value \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unsecured notes payable and Unsecured line of credit, net	$ 515,330	$ 435,779

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Common Shares, Share Repurchases and Dividends and Distributions (Details) - USD ($)				1 Months Ended	3 Months Ended								12 Months Ended
	Nov. 08, 2017	Nov. 08, 2016	Nov. 07, 2016	Jul. 31, 2016	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2001	May 10, 2017	May 09, 2017	Dec. 31, 2014
Class of Stock [Line Items]
Common shares, authorized (in shares)					200,000,000				100,000,000				200,000,000	100,000,000			200,000,000	100,000,000
Authorized amount					$ 20,000,000.0								$ 20,000,000.0
Treasury stock, acquired (in shares)													0	0		2,100,000
Remaining authorized repurchase amount					$ 7,500,000								$ 7,500,000
Distributions declared (in dollars per share)					$ 0.27	$ 0.26	$ 0.26	$ 0.26	$ 0.41	$ 0.25	$ 0.25	$ 0.25	$ 1.05	$ 1.16	$ 1.22
ATM Equity Program
Class of Stock [Line Items]
Stock, shares authorized not issued																			$ 200,000,000.0
Restricted Stock
Class of Stock [Line Items]
Restricted stock, shares canceled for tax withholding for share based compensation (in shares)													4,314	3,152
LTIP Units and Restricted Stock
Class of Stock [Line Items]
Unit based compensation													$ 8,400,000	$ 10,900,000
Common Shares
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)														4,830,000
Stock issued during period														$ 175,200,000
Proceeds from issuance of common stock														$ 172,100,000
Common Shares \| Forward Sale and Underwritten Public Offering
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)														3,600,000
Stock issued during period														$ 126,800,000
Proceeds from issuance of common stock														$ 124,500,000
Common Shares \| ATM Equity Program
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)														4,500,000
Stock issued during period														$ 157,600,000
Proceeds from issuance of common stock														155,700,000
Additional maximum gross proceeds amount				$ 250,000,000.0									250,000,000	250,000,000.0
Sale of Stock, remaining value under program													$ 218,000,000	$ 218,000,000
Regular Quarterly Cash Dividend
Class of Stock [Line Items]
Cash dividends declared, period increase (in dollars per share)	$ 0.01	$ 0.01
Distributions declared (in dollars per share)	$ 0.27	0.26	$ 0.25
Special Cash Dividend
Class of Stock [Line Items]
Cash dividends paid (in dollars per share)		$ 0.15

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	$ 2,178,125	$ 1,521,354	$ 1,435,957
Other comprehensive loss before reclassifications	634	(646)
Reclassification of realized interest on swap agreements	3,317	4,576
Net current period other comprehensive loss	3,951	3,930	463
Ending Balance	2,215,639	2,178,125	1,521,354
AOCI Attributable to Parent
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	(798)	(4,463)	(4,005)
Ending Balance	2,614	(798)	$ (4,463)
AOCI Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Net current period other comprehensive loss	$ (539)	$ (265)

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Noncontrolling Interest (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance				$ 589,548					$ 589,548
Net income (loss)	$ 24,944	$ 13,285	$ 6,108	$ 19,971	$ 34,236	$ 326	$ 26,155	$ 73,875	64,308	$ 134,592	$ 149,970
Conversion of Common OP Units to Common Shares by limited partners of the Operating Partnership									0	0	0
Issuance of OP Units to acquire real estate										31,429
Acquisition of noncontrolling interests										(18,379)	(7,970)
Other comprehensive income - unrealized loss on valuation of swap agreements									634	(646)	(5,061)
Change in control of previously unconsolidated investment										(75,713)
Reclassification of realized interest on swap agreements									3,317	4,576	5,524
Noncontrolling interest contributions									85,206	295,108	35,489
Noncontrolling interest distributions									(32,805)	(80,769)	(74,950)
Employee Long-term Incentive Plan Unit Awards									11,155	13,694	8,644
Rebalancing adjustment									0	0
Balance	$ 648,440				$ 589,548				648,440	589,548
Payments to noncontrolling interests									$ 39,942	$ 105,994	$ 84,610
Distributions declared (in dollars per share)	$ 0.27	$ 0.26	$ 0.26	$ 0.26	$ 0.41	$ 0.25	$ 0.25	$ 0.25	$ 1.05	$ 1.16	$ 1.22
Preferred shares converted to common stock (in shares)	5,000								5,000
Limited partners' capital account, units issued and converted (in shares)	81,453				351,250				81,453	351,250
Fund II
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Additional ownership interest acquired								8.30%
Payments to noncontrolling interests								$ 18,400
Equity Interest Held By Operating Partnership								28.33%
LTIP Units
Increase (Decrease) in Stockholders' Equity [Roll Forward]
LTIP units outstanding (in shares)	2,274,147				1,997,099				2,274,147	1,997,099
Series A Preferred Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Limited partners' capital account, units issued and converted (in shares)	1,392								1,392
Restatement Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance				$ (35,700)				$ (31,800)	$ (35,700)	$ (31,800)
Net income (loss)					$ (4,200)					(4,200)
Balance					$ (35,700)					$ (35,700)	$ (31,800)
Operating Partnership, as General Partner or Managing Member
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Series A Preferred OP Units (in shares)	3,328,873				3,308,875				3,328,873	3,308,875
Equity Interest Held By Operating Partnership									95.00%	95.00%
Operating Partnership, as General Partner or Managing Member \| Series A Preferred Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Series A Preferred OP Units (in shares)	188				188				188	188
Operating Partnership, as General Partner or Managing Member \| Series C Preferred Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Series A Preferred OP Units (in shares)	136,593				141,593				136,593	141,593
Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance				589,548				420,866	$ 589,548	$ 420,866
Distributions declared of $0.78 and $1.16 per Common OP Unit for Years Ended 2017 and 2016, respectively									(6,453)	(6,753)
Net income (loss)									2,838	61,816
Conversion of Common OP Units to Common Shares by limited partners of the Operating Partnership									(1,541)	(7,892)	(2,451)
Issuance of OP Units to acquire real estate										31,429
Acquisition of noncontrolling interests										(25,925)	(3,561)
Other comprehensive income - unrealized loss on valuation of swap agreements									(147)	(332)
Change in control of previously unconsolidated investment										(75,713)
Reclassification of realized interest on swap agreements									686	597
Noncontrolling interest contributions									85,206	295,108	35,489
Noncontrolling interest distributions									(32,805)	(80,769)	(74,950)
Employee Long-term Incentive Plan Unit Awards									10,457	12,768	6,723
Rebalancing adjustment									651	(35,652)
Balance	$ 648,440				$ 589,548				648,440	589,548	420,866
Noncontrolling Interests \| Restatement Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance	651								651
Noncontrolling Interests \| Noncontrolling Interests in Partially-Owned Affiliates
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance				494,126				324,526	494,126	324,526
Distributions declared of $0.78 and $1.16 per Common OP Unit for Years Ended 2017 and 2016, respectively									0	0
Net income (loss)									(1,321)	56,814
Conversion of Common OP Units to Common Shares by limited partners of the Operating Partnership									0	0
Issuance of OP Units to acquire real estate										0
Acquisition of noncontrolling interests										(25,925)
Other comprehensive income - unrealized loss on valuation of swap agreements									(232)	(289)
Change in control of previously unconsolidated investment										(75,713)
Reclassification of realized interest on swap agreements									545	374
Noncontrolling interest contributions									85,206	295,108
Noncontrolling interest distributions									(32,805)	(80,769)
Employee Long-term Incentive Plan Unit Awards									0	0
Rebalancing adjustment										0
Balance	545,519				494,126				545,519	494,126	324,526
Noncontrolling Interests \| Noncontrolling Interests in Partially-Owned Affiliates \| Restatement Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance	0								0
Noncontrolling Interests \| Operating Partnership, as General Partner or Managing Member
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance				$ 95,422				$ 96,340	95,422	96,340
Distributions declared of $0.78 and $1.16 per Common OP Unit for Years Ended 2017 and 2016, respectively									(6,453)	(6,753)
Net income (loss)									4,159	5,002
Conversion of Common OP Units to Common Shares by limited partners of the Operating Partnership									(1,541)	(7,892)
Issuance of OP Units to acquire real estate										31,429
Acquisition of noncontrolling interests										0
Other comprehensive income - unrealized loss on valuation of swap agreements									85	(43)
Change in control of previously unconsolidated investment										0
Reclassification of realized interest on swap agreements									141	223
Noncontrolling interest contributions									0	0
Noncontrolling interest distributions									0	0
Employee Long-term Incentive Plan Unit Awards									10,457	12,768
Rebalancing adjustment										(35,652)
Balance	102,921				$ 95,422				102,921	$ 95,422	$ 96,340
Noncontrolling Interests \| Operating Partnership, as General Partner or Managing Member \| Restatement Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance	$ 651								$ 651

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Preferred OP Units (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2016 $ / shares shares	Dec. 31, 2017 USD ($) $ / Units shares	Dec. 31, 2016 shares	Dec. 31, 1999 shares
Class of Stock [Line Items]
Limited partners' capital account, units issued and converted (in shares)		81,453	351,250
Units converted from Series A Preferred OP Units (in shares)		185,600
Denominator for Series A Preferred OP Unit conversion \| $		$ 7.50
Preferred OP Units
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)		0
Series C Preferred OP Units
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)		5,000
Series A Preferred Stock
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)				1,580
Preferred stock, stated value per unit \| $ / Units		1,000
Per unit conversion amount, Series A Preferred OP Units (in dollars per unit) \| $ / Units		22.50
Per unit conversion annual rate, Preferred OP Units		9.00%
Limited partners' capital account, units issued and converted (in shares)		1,392
Common Shares
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)			4,830,000
Operating Partnership, as General Partner or Managing Member
Class of Stock [Line Items]
Preferred OP Units (in shares)		3,328,873	3,308,875
Operating Partnership, as General Partner or Managing Member \| Series A Preferred Stock
Class of Stock [Line Items]
Preferred OP Units (in shares)		188	188
Gotham Plaza \| Preferred OP Units
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)	141,593
Gotham Plaza \| Common Shares
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)	442,478
Share price (in dollars per share) \| $ / shares	$ 100.00
Preferred quarterly distribution per share price \| $ / shares	$ 0.9375
Number of convertible units if share price falls below $28.80 (in shares)	3.4722
Number of convertible units of share price falls above $35.20 (in Shares)	2.8409
Minimum \| Gotham Plaza \| Preferred OP Units
Class of Stock [Line Items]
Share price at conversion date \| $ / shares	$ 28.80
Maximum \| Gotham Plaza \| Preferred OP Units
Class of Stock [Line Items]
Share price at conversion date \| $ / shares	$ 35.20

Leases - Operating Leases (Details) $ in Millions	12 Months Ended
Leases - Operating Leases (Details) $ in Millions	Dec. 31, 2017 USD ($) shopping_center	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Operating Leased Assets [Line Items]
Number of shopping centers with land leases \| shopping_center	7
Ground lease expense	$ 1.4	$ 1.2	$ 1.7
Rent expense capitalized	0.1	0.6	0.9
Rent expense	$ 1.0	$ 1.0	$ 1.4
Minimum
Operating Leased Assets [Line Items]
Period of lease term	25 years
Maximum
Operating Leased Assets [Line Items]
Period of lease term	71 years

Leases - Capital Leasers (Details) - USD ($) $ in Thousands	12 Months Ended
Leases - Capital Leasers (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Capital Leased Assets [Line Items]
Capital lease obligation	$ 70,611	$ 70,129
991 Madison Avenue New York, NY
Capital Leased Assets [Line Items]
Capital lease term	49 years
Capital lease obligation	$ 76,600
991 Madison Avenue New York, NY \| Capital Lease Obligations
Capital Leased Assets [Line Items]
Repayments capital lease obligations	$ 2,500	$ 1,300

Leases - Lease Obligations (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Minimum Rental Revenues
2018	$ 165,893
2019	163,576
2020	149,453
2021	130,834
2022	111,958
Thereafter	514,271
Total	1,235,985
Minimum Rental Payments
2018	4,540
2019	4,560
2020	4,356
2021	4,302
2022	4,395
Thereafter	185,014
Total	$ 207,167

Segment Reporting (Details) $ in Thousands	3 Months Ended								12 Months Ended
Segment Reporting (Details) $ in Thousands	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) segment	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment									3
Revenues	$ 66,081	$ 62,678	$ 59,504	$ 61,999	$ 54,121	$ 43,855	$ 43,918	$ 48,045	$ 250,262	$ 189,939	$ 199,063
Depreciation and amortization									(104,934)	(70,011)	(60,751)
Property operating expenses, other operating and real estate taxes									(79,798)	(57,391)	(58,482)
Impairment charges	(10,600)	(3,800)							(14,455)	0	(5,000)
General and administrative expenses									(33,756)	(40,648)	(30,368)
Operating income									17,319	21,889	44,462
Gain on disposition of properties									48,886	81,965	89,063
Interest income									29,143	25,829	16,603
Equity in earnings (losses) of unconsolidated affiliates									23,371	39,449	37,330
Other											1,596
Interest expense									(58,978)	(34,645)	(37,297)
Gain on change in control									5,571	0	0
Income tax (provision) benefit									(1,004)	105	(1,787)
Net income	24,944	13,285	6,108	19,971	34,236	326	26,155	73,875	64,308	134,592	149,970
Net income attributable to noncontrolling interests	(4,032)	(418)	5,952	(4,340)	(14,415)	5,786	(8,237)	(44,950)	(2,838)	(61,816)	(84,262)
Net income attributable to Acadia	20,912	$ 12,867	$ 12,060	$ 15,631	19,821	$ 6,112	$ 17,918	$ 28,925	61,470	72,776	65,708
Real estate at cost	3,466,482				3,382,000				3,466,482	3,382,000	2,736,283
Total assets	3,960,247				3,995,960				3,960,247	3,995,960	3,032,319
Cash paid for acquisition of real estate									200,429	495,644	338,700
Cash paid for development and property improvement costs									115,455	149,434	164,315
Operating segments \| Core Portfolio
Segment Reporting Information [Line Items]
Revenues									169,975	150,211	150,015
Depreciation and amortization									(61,705)	(54,582)	(46,223)
Property operating expenses, other operating and real estate taxes									(45,349)	(39,598)	(37,259)
Impairment charges									0		(5,000)
General and administrative expenses									0	0	0
Operating income									62,921	56,031	61,533
Gain on disposition of properties									0	0	0
Interest income									0	0	0
Equity in earnings (losses) of unconsolidated affiliates									3,735	3,774	1,169
Other											0
Interest expense									(28,618)	(27,435)	(27,945)
Gain on change in control									5,571
Income tax (provision) benefit									0	0	0
Net income									43,609	32,370	34,757
Net income attributable to noncontrolling interests									(1,107)	(3,411)	(140)
Net income attributable to Acadia									42,502	28,959	34,617
Real estate at cost	2,032,485				1,982,763				2,032,485	1,982,763	1,572,681
Total assets	2,305,663				2,271,620				2,305,663	2,271,620	1,662,092
Cash paid for acquisition of real estate									0	323,880	181,884
Cash paid for development and property improvement costs									49,339	13,434	16,505
Operating segments \| Funds
Segment Reporting Information [Line Items]
Revenues									80,287	39,728	49,048
Depreciation and amortization									(43,229)	(15,429)	(14,528)
Property operating expenses, other operating and real estate taxes									(34,449)	(17,793)	(21,223)
Impairment charges									(14,455)		0
General and administrative expenses									0	0	0
Operating income									(11,846)	6,506	13,297
Gain on disposition of properties									48,886	81,965	89,063
Interest income									0	0	0
Equity in earnings (losses) of unconsolidated affiliates									19,636	35,675	36,161
Other											0
Interest expense									(30,360)	(7,210)	(9,352)
Gain on change in control									0
Income tax (provision) benefit									0	0	0
Net income									26,316	116,936	129,169
Net income attributable to noncontrolling interests									(1,731)	(58,405)	(84,122)
Net income attributable to Acadia									24,585	58,531	45,047
Real estate at cost	1,433,997				1,399,237				1,433,997	1,399,237	1,163,602
Total assets	1,500,755				1,448,177				1,500,755	1,448,177	1,223,039
Cash paid for acquisition of real estate									200,429	171,764	156,816
Cash paid for development and property improvement costs									66,116	136,000	147,810
Operating segments \| Structured Financing
Segment Reporting Information [Line Items]
Revenues									0	0	0
Depreciation and amortization									0	0	0
Property operating expenses, other operating and real estate taxes									0	0	0
Impairment charges									0		0
General and administrative expenses									0	0	0
Operating income									0	0	0
Gain on disposition of properties									0	0	0
Interest income									29,143	25,829	16,603
Equity in earnings (losses) of unconsolidated affiliates									0	0	0
Other											1,596
Interest expense									0	0	0
Gain on change in control									0
Income tax (provision) benefit									0	0	0
Net income									29,143	25,829	18,199
Net income attributable to noncontrolling interests									0	0	0
Net income attributable to Acadia									29,143	25,829	18,199
Real estate at cost	0				0				0	0	0
Total assets	153,829				276,163				153,829	276,163	147,188
Cash paid for acquisition of real estate									0	0	0
Cash paid for development and property improvement costs									0	0	0
Unallocated
Segment Reporting Information [Line Items]
Revenues									0	0	0
Depreciation and amortization									0	0	0
Property operating expenses, other operating and real estate taxes									0	0	0
Impairment charges									0		0
General and administrative expenses									(33,756)	(40,648)	(30,368)
Operating income									(33,756)	(40,648)	(30,368)
Gain on disposition of properties									0	0	0
Interest income									0	0	0
Equity in earnings (losses) of unconsolidated affiliates									0	0	0
Other											0
Interest expense									0	0	0
Gain on change in control									0
Income tax (provision) benefit									(1,004)	105	(1,787)
Net income									(34,760)	(40,543)	(32,155)
Net income attributable to noncontrolling interests									0	0	0
Net income attributable to Acadia									(34,760)	(40,543)	(32,155)
Real estate at cost	0				0				0	0	0
Total assets	$ 0				$ 0				0	0	0
Cash paid for acquisition of real estate									0	0	0
Cash paid for development and property improvement costs									$ 0	$ 0	$ 0

Share Incentive and Other Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 0.2	$ 0.2
Trustee fees	1.2	1.1
Total unrecognized compensation cost related to nonvested awards	$ 14.3
Weighted-average period over which cost is expected to be recognized	2 years 2 months
LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of shares that vested	$ 7.3	13.6
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of shares that vested	0.7	0.7
LTIP Units and Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total value of restricted shares and LTIP units as of the grant date	9.5
Compensation expense	7.3	2.2
Unit based compensation	$ 8.4	$ 10.9
Weighted average grant date fair value, grants (in dollars per share)	$ 31.69	$ 34.34
Officers and Employees \| Second Amended 2016 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	1,756,317
Officer \| LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures	306,635
Officer \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures	7,628
Trustee \| LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures	11,105
Trustee \| LTIP Units \| Tranche 1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures	5,805
Trustee \| LTIP Units \| Tranche 2
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures	5,300
Senior Executives \| Long Term Investment Alignment Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Max percentage of future fund III promote that may be awarded to senior executives			25.00%
General and Administrative Expense \| LTIP Units and Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit based compensation	$ 8.4	$ 10.9
Trustee \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures	11,814
Shares granted to trustees for trustee fees vesting on one year anniversary of grant date	3,864
Shares granted to trustees for trustee fees begin vesting on two year anniversary of grant date	7,950
Trustee \| LTIP Units and Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Annual vesting rate of shares granted to trustees that begin vesting on the second anniversary of grant date	33.00%
Fund III \| Long Term Investment Alignment Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 0.6	$ 5.0
Fund III \| Senior Executives \| Long Term Investment Alignment Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of promote awarded as share based compensation award			25.00%
Fund IV \| Senior Executives \| Long Term Investment Alignment Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of promote awarded as share based compensation award			14.40%

Share Incentive and Other Compensation - Schedule of Unvested Shares and LTIP Units (Details) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Shares unvested, Beginning of period (in shares)	46,499	49,899
Shares granted (in shares)	19,442	21,675
Shares vested (in shares)	(23,430)	(24,886)
Shares forfeited (in shares)	(1,184)	(189)
Shares unvested, End of period (in shares)	41,327	46,499
Weighted Grant-Date Fair Value
Shares unvested, Weighted average grant date fair value, Beginning of period (in dollars per share)	$ 27.58	$ 25.90
Shares granted, Weighted average grant date fair value (in dollars per share)	29.85	33.35
Shares vested, Weighted average grant date fair value (in dollars per share)	30.47	29.17
Shares forfeited, Weighted average grant date fair value (in dollars per share)	32.65	35.37
Shares unvested, Weighted average grant date fair value, End of period (in dollars per share)	$ 26.92	$ 27.58
LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Shares unvested, Beginning of period (in shares)	856,877	1,020,121
Shares granted (in shares)	310,551	359,484
Shares vested (in shares)	(257,124)	(522,680)
Shares forfeited (in shares)	(205)	(48)
Shares unvested, End of period (in shares)	910,099	856,877
Weighted Grant-Date Fair Value
Shares unvested, Weighted average grant date fair value, Beginning of period (in dollars per share)	$ 26.99	$ 23.92
Shares granted, Weighted average grant date fair value (in dollars per share)	31.80	34.40
Shares vested, Weighted average grant date fair value (in dollars per share)	28.27	26.08
Shares forfeited, Weighted average grant date fair value (in dollars per share)	32.49	35.37
Shares unvested, Weighted average grant date fair value, End of period (in dollars per share)	$ 28.28	$ 26.99

Share Incentive and Other Compensation - Employee Share Purchase Plan and Deferred Share Plan (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee share purchase discount rate	15.00%
Employee share purchase maximum purchase amount	$ 25
Common Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee share purchase (in shares)	4,514	4,016

Share Incentive and Other Compensation - Employee 401 (k) Plan (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($)
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Employer matching contribution	50.00%
Maximum annual contribution per employee	6.00%
Maximum employee annual salary contribution	15.00%
Maximum employee annual salary contribution amount	$ 18

Federal Income Taxes - Reconciliation of Net Income to Taxable Income (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Net income attributable to Acadia	$ 20,912	$ 12,867	$ 12,060	$ 15,631	$ 19,821	$ 6,112	$ 17,918	$ 28,925	$ 61,470	$ 72,776	$ 65,708
Deferred cancellation of indebtedness income									2,050	2,050	2,050
Deferred rental and other income									(934)	1,610	82
Book/tax difference - depreciation and amortization									21,334	15,189	9,983
Straight-line rent and above- and below-market rent adjustments									(10,559)	(7,882)	(8,041)
Book/tax differences - equity-based compensation									5,325	10,307	5,833
Joint venture equity in earnings, net									9,114	(2,011)	5,776
Impairment charges and reserves									0	769	(714)
Acquisition costs									1,135	5,116	1,190
Gains									(5,181)	0	(760)
Book/tax differences - miscellaneous									930	(4,924)	2,573
Taxable income									84,684	93,000	83,680
Distributions declared									$ 87,848	$ 91,053	$ 84,683

Federal Income Taxes - Tax Status of Dividends (Details) - $ / shares	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Ordinary income (in dollars per share)									$ 0.82	$ 0.77	$ 0.83
Qualified dividend (in dollars per share)									0.00	0.00	0.00
Capital gain (in dollars per share)									0.23	0.39	0.39
Total (in dollars per share)	$ 0.27	$ 0.26	$ 0.26	$ 0.26	$ 0.41	$ 0.25	$ 0.25	$ 0.25	$ 1.05	$ 1.16	$ 1.22
Ordinary income									78.00%	66.00%	68.00%
Qualified dividend									0.00%	0.00%	0.00%
Capital gain									22.00%	34.00%	32.00%
Total									100.00%	100.00%	100.00%

Federal Income Taxes - Income and Provision for Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Contingency [Line Items]
TRS income (loss) before income taxes									$ 16,426	$ 52,522	$ 62,694
(Provision) benefit for income taxes:
TRS net income (loss) before noncontrolling interests									61,470	72,776	65,708
Noncontrolling interests	$ (4,032)	$ (418)	$ 5,952	$ (4,340)	$ (14,415)	$ 5,786	$ (8,237)	$ (44,950)	(2,838)	(61,816)	(84,262)
Net income	$ 24,944	$ 13,285	$ 6,108	$ 19,971	$ 34,236	$ 326	$ 26,155	$ 73,875	64,308	134,592	149,970
TRS [Member]
Income Tax Contingency [Line Items]
TRS income (loss) before income taxes									(3,604)	(1,583)	1,008
(Provision) benefit for income taxes:
Federal									(982)	378	(526)
State and local									423	97	(134)
TRS net income (loss) before noncontrolling interests									(4,163)	(1,108)	348
Noncontrolling interests									8	(9)	(208)
Net income									$ (4,155)	$ (1,117)	$ 140

Federal Income Taxes - Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Federal tax provision (benefit) at statutory tax rate	$ (1,225)	$ (538)	$ 343
TRS state and local taxes, net of Federal benefit	(190)	(84)	53
Permanent differences, net	1,131	1,663	396
Prior year (over) under-accrual, net	(1,541)	0	938
Effect of Tax Cuts and Jobs Act	1,982	0	0
Other	404	(1,516)	(131)
REIT state and local income and franchise taxes	443	370	188
Total provision (benefit) for income taxes	$ 1,004	$ (105)	$ 1,787

Federal Income Taxes - Additional Information (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Deferred tax assets, additional tax basis in RCP Investments	$ 1,000,000	$ 1,700,000
Deferred tax assets, deferred interest	0	800,000
Deferred tax assets, operating loss carryforwards	$ 1,100,000	$ 1,300,000

Earnings Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Numerator:
Net income attributable to Acadia									$ 61,470	$ 72,776	$ 65,708
Less: net income attributable to participating securities									(642)	(793)	(927)
Income from continuing operations net of income attributable to participating securities									$ 60,828	$ 71,983	$ 64,781
Denominator:
Weighted average shares for basic earnings per share (in shares)									83,682,789	76,231,000	68,851,083
Effect of dilutive securities:
Employee unvested restricted shares (in shares)									2,682	12,550	18,556
Denominator for diluted earnings per share (in shares)	83,733,000	83,700,000	83,662,000	83,646,000	82,728,000	78,624,000	72,896,000	71,215,000	83,685,471	76,243,550	68,869,639
Basic and diluted earnings per share (in dollars per share)									$ 0.73	$ 0.94	$ 0.94
Series A Preferred OP Units
Anti-Dilutive Shares Excluded from Denominator:
Antidilutive securities excluded from computation of earnings per share (in shares)									188	188	188
Series A Preferred OP Units - Common share equivalent
Anti-Dilutive Shares Excluded from Denominator:
Antidilutive securities excluded from computation of earnings per share (in shares)									25,067	25,067	25,067
Series C Preferred OP Units
Anti-Dilutive Shares Excluded from Denominator:
Antidilutive securities excluded from computation of earnings per share (in shares)									136,593	141,593	0
Series C Preferred OP Units - Common share equivalent
Anti-Dilutive Shares Excluded from Denominator:
Antidilutive securities excluded from computation of earnings per share (in shares)									479,978	410,207	0

Summary of Quarterly Financial Information (Unaudited) (Details) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017 USD ($) property $ / shares shares	Sep. 30, 2017 USD ($) property $ / shares shares	Jun. 30, 2017 USD ($) $ / shares shares	Mar. 31, 2017 USD ($) property $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Sep. 30, 2016 USD ($) $ / shares shares	Jun. 30, 2016 USD ($) $ / shares shares	Mar. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) property $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares
Interim Period, Costs Not Allocable [Line Items]
Revenue	$ 66,081	$ 62,678	$ 59,504	$ 61,999	$ 54,121	$ 43,855	$ 43,918	$ 48,045	$ 250,262	$ 189,939	$ 199,063
Net income (loss)	24,944	13,285	6,108	19,971	34,236	326	26,155	73,875	64,308	134,592	149,970
Net income attributable to noncontrolling interests	(4,032)	(418)	5,952	(4,340)	(14,415)	5,786	(8,237)	(44,950)	(2,838)	(61,816)	(84,262)
Net income attributable to Acadia	$ 20,912	$ 12,867	$ 12,060	$ 15,631	$ 19,821	$ 6,112	$ 17,918	$ 28,925	$ 61,470	$ 72,776	$ 65,708
Basic (in dollars per share) \| $ / shares	$ 0.25	$ 0.15	$ 0.14	$ 0.18	$ 0.24	$ 0.08	$ 0.24	$ 0.40
Diluted (in dollars per share) \| $ / shares	$ 0.25	$ 0.15	$ 0.14	$ 0.18	$ 0.24	$ 0.08	$ 0.24	$ 0.40
Weighted average number of shares: Basic \| shares	83,733,000	83,700,000	83,662,000	83,635,000	82,728,000	78,449,000	72,896,000	70,756,000
Weighted average number of shares: Diluted \| shares	83,733,000	83,700,000	83,662,000	83,646,000	82,728,000	78,624,000	72,896,000	71,215,000	83,685,471	76,243,550	68,869,639
Cash dividends declared per common share (in dollars per share) \| $ / shares	$ 0.27	$ 0.26	$ 0.26	$ 0.26	$ 0.41	$ 0.25	$ 0.25	$ 0.25	$ 1.05	$ 1.16	$ 1.22
Impairment charges	$ 10,600	$ 3,800							$ 14,455	$ 0	$ 5,000
Gain on change in control and other	5,600								5,571	0	$ 1,596
Equity method investment, ownership percentage								65.00%
Noncontrolling Interests
Interim Period, Costs Not Allocable [Line Items]
Net income (loss)									$ 2,838	61,816
Impairment charges	7,600	2,700
Cortlandt Towne Center \| Fund III
Interim Period, Costs Not Allocable [Line Items]
Gain/(Loss) on sale								$ 65,400
Cortlandt Towne Center \| Fund III \| Noncontrolling Interests
Interim Period, Costs Not Allocable [Line Items]
Gain/(Loss) on sale								$ 49,400
Heritage Shops \| Fund III
Interim Period, Costs Not Allocable [Line Items]
Gain/(Loss) on sale							$ 16,600
Heritage Shops \| Fund III \| Noncontrolling Interests
Interim Period, Costs Not Allocable [Line Items]
Gain/(Loss) on sale							$ 12,500
Restatement Adjustment
Interim Period, Costs Not Allocable [Line Items]
Net income (loss)					$ (4,200)					(4,200)
Net income attributable to noncontrolling interests					$ 1,600					$ 1,600
Disposed of by sale
Interim Period, Costs Not Allocable [Line Items]
Gain (loss) on disposal	$ 35,900	$ 13,000	$ 3,300	$ 14,500
Number of retail properties \| property	3	2		2					3
Disposed of by sale \| Noncontrolling Interests
Interim Period, Costs Not Allocable [Line Items]
Gain (loss) on disposal	$ 26,700	$ 10,700
Disposed of by sale \| Partnership Interest
Interim Period, Costs Not Allocable [Line Items]
Gain (loss) on disposal			$ 800	$ 2,700

Subsequent Events (Details) - USD ($)				12 Months Ended
Subsequent Events (Details) - USD ($)	Feb. 21, 2018	Jan. 24, 2018	Jan. 18, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Feb. 20, 2018	Jan. 29, 2018
Subsequent Event [Line Items]
Purchase Price				$ 254,532,000	$ 756,842,000
Proceeds from the disposition of properties				260,711,000	150,378,000	$ 168,895,000
Proceeds from notes receivable				32,000,000	42,819,000	$ 15,984,000
Stock repurchase authorized amount				20,000,000.0
Fund V
Subsequent Event [Line Items]
Purchase Price				167,240,000
Fund IV
Subsequent Event [Line Items]
Purchase Price				44,492,000	237,250,000
Mortgages
Subsequent Event [Line Items]
Borrowings, amount				162,900,000.0
Core Portfolio
Subsequent Event [Line Items]
Purchase Price				42,800,000	$ 519,592,000
Core Portfolio \| $150 Million Term Loan \| Unsecured Debt
Subsequent Event [Line Items]
Maximum borrowing capacity				$ 150,000,000.0
Subsequent Event
Subsequent Event [Line Items]
Maximum borrowing capacity							$ 300,000,000.0
Stock repurchase authorized amount							200,000,000.0
Subsequent Event \| Other Secured Financings
Subsequent Event [Line Items]
Maximum borrowing capacity							40,400,000.0
Subsequent Event \| 108 W. Broughton And 110 W. Broughton Street Properties \| Fund IV \| Disposed of by sale
Subsequent Event [Line Items]
Proceeds from the disposition of properties			$ 8,000,000
Subsequent Event \| Plaza Santa Fe \| Mortgages \| Fund V
Subsequent Event [Line Items]
Borrowings, amount		$ 22,900,000.0
Subsequent Event \| New Towne Plaza \| Mortgages \| Fund V
Subsequent Event [Line Items]
Borrowings, amount								$ 16,900,000.0
Subsequent Event \| Senior Unsecured Credit Facility \| Unsecured Debt
Subsequent Event [Line Items]
Maximum borrowing capacity							500,000,000.0
Subsequent Event \| Revolving Credit Facility \| Unsecured Debt
Subsequent Event [Line Items]
Maximum borrowing capacity							150,000,000.0
Subsequent Event \| $300 Million Term Loan \| Unsecured Debt
Subsequent Event [Line Items]
Maximum borrowing capacity							350,000,000.0
Subsequent Event \| $150 Million Term Loan \| Unsecured Debt
Subsequent Event [Line Items]
Maximum borrowing capacity							150,000,000.0
Subsequent Event \| Trussville, Alabama \| Shopping Center \| Fund V
Subsequent Event [Line Items]
Purchase Price	$ 45,200,000
Subsequent Event \| Core Portfolio
Subsequent Event [Line Items]
Proceeds from notes receivable		$ 26,000,000
Subsequent Event \| Core Portfolio \| Revolving Credit Facility \| Unsecured Debt
Subsequent Event [Line Items]
Maximum borrowing capacity							150,000,000.0
Subsequent Event \| Core Portfolio \| $150 Million Term Loan \| Unsecured Debt
Subsequent Event [Line Items]
Maximum borrowing capacity							$ 150,000,000.0

SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance for deferred tax asset
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 859	$ 0	$ 0
Charged to Expenses	0	0	0
Adjustments to Valuation Accounts	671	859	0
Deductions	0	0	0
Balance at End of Year	1,530	859	0
Allowance for uncollectible accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	5,720	7,451	5,952
Charged to Expenses	200	0	1,499
Adjustments to Valuation Accounts	0	0	0
Deductions	0	(1,731)	0
Balance at End of Year	5,920	5,720	7,451
Allowance for notes receivable
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	0	0	0
Charged to Expenses	0	0	0
Adjustments to Valuation Accounts	0	0	0
Deductions	0	0	0
Balance at End of Year	$ 0	$ 0	$ 0

SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION - Reconciliation of Real Estate Properties (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at beginning of year	$ 3,382,000	$ 2,736,283	$ 2,208,595
Other improvements	55,763	152,129	162,760
Property acquisitions	179,292	761,400	418,396
Property dispositions or held for sale assets	(189,895)	(134,332)	(66,359)
Prior year purchase price allocation adjustments	0	(9,844)	0
Deconsolidation of previously consolidated investments	0	(123,636)	0
Consolidation of previously unconsolidated investments	39,322	0	12,891
Balance at end of year	$ 3,466,482	$ 3,382,000	$ 2,736,283

SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION - Reconciliation of Accumulated Depreciation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at beginning of year	$ 287,066	$ 298,703	$ 256,015
Depreciation related to real estate	73,268	49,269	49,775
Property dispositions	(20,472)	(27,829)	(7,087)
Deconsolidation of previously consolidated investments	0	(33,077)	0
Balance at end of year	$ 339,862	$ 287,066	$ 298,703

SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE - Loans On Real Estate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Mortgage Loans on Real Estate [Line Items]
Face Amount of Notes Receivable	$ 241,200
Net carrying amount of notes receivable	$ 153,829	$ 276,163
First Mortgage Loan, 6.0% Loan, Due 6/1/2018
Mortgage Loans on Real Estate [Line Items]
Effective Interest Rate	6.00%
Face Amount of Notes Receivable	$ 15,000
Net carrying amount of notes receivable	$ 15,000
First Mortgage Loan LIBOR Plus 7.1% Due 6/252018
Mortgage Loans on Real Estate [Line Items]
Basis spread on variable rate	7.10%
Face Amount of Notes Receivable	$ 26,000
Net carrying amount of notes receivable	$ 26,000
First Mortgage Loan, 8.1% Loan, Due 2019
Mortgage Loans on Real Estate [Line Items]
Effective Interest Rate	8.10%
Face Amount of Notes Receivable	$ 153,400
Net carrying amount of notes receivable	$ 60,695
Zero Coupon Loan Due 5/31/2020
Mortgage Loans on Real Estate [Line Items]
Effective Interest Rate	2.50%
Face Amount of Notes Receivable	$ 29,793
Net carrying amount of notes receivable	$ 31,778
Mezzanine Loan 18.0% Loan Due 7/1/2020
Mortgage Loans on Real Estate [Line Items]
Effective Interest Rate	18.00%
Face Amount of Notes Receivable	$ 3,007
Net carrying amount of notes receivable	$ 5,106
Preferred Equity, 15.3% Loan, Due 2/3/2021
Mortgage Loans on Real Estate [Line Items]
Effective Interest Rate	15.30%
Face Amount of Notes Receivable	$ 14,000
Net carrying amount of notes receivable	$ 15,250

SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE - Reconciliation of Loans on Real Estate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Movement in Mortgage Loans on Real Estate [Roll Forward]
Balance at beginning of year	$ 276,163	$ 147,188	$ 102,286
Additions	11,371	171,794	48,500
Disposition of air rights through issuance of notes	0	0	29,539
Repayments	(32,000)	(42,819)	(15,984)
Conversion to real estate through receipt of deed or through foreclosure	(101,705)	0	(13,386)
Other	0	0	(3,767)
Balance at end of year	$ 153,829	$ 276,163	$ 147,188

CONSOLIDATED STATEMENTS OF INCOME (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Gains (losses) on disposition of properties	$ 15,336	$ 35,950	$ 24,043

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Cash Flows [Abstract]
Cash paid for capitalized interest	$ 13,509	$ 21,109	$ 16,447
Payments of stock issuance costs	$ 0	$ 92,838	$ 1,150

Commitments and Contingencies (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Contractual obligation	$ 92.2	$ 85.4
Letters of credit, outstanding amount	$ 19.7	$ 11.3