Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2018	Jun. 30, 2018	Feb. 13, 2018
Document And Entity Information [Abstract]
Entity Registrant Name	ACADIA REALTY TRUST
Entity Central Index Key	0000899629
Current Fiscal Year End Date	--12-31
Trading Symbol	AKR
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Document Type	10-K
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Common Stock, Shares Outstanding			81,703,355
Entity Public Float		$ 2,230.7
Entity Shell Company	false
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
ASSETS
Operating real estate, net	$ 3,160,851	$ 2,952,918
Real estate under development	120,297	173,702
Net investments in real estate	3,281,148	3,126,620
Notes receivable, net	109,613	153,829
Investments in and advances to unconsolidated affiliates	262,410	302,070
Other assets, net	208,570	214,959
Cash and cash equivalents	21,268	74,823
Rents receivable, net	62,191	51,738
Restricted cash	13,580	10,846
Assets of properties held for sale	0	25,362
Total assets	3,958,780	3,960,247
LIABILITIES
Mortgage and other notes payable, net	1,017,288	909,174
Unsecured notes payable, net	533,257	473,735
Unsecured line of credit	0	41,500
Accounts payable and other liabilities	214,961	210,052
Capital lease obligation	71,111	70,611
Dividends and distributions payable	24,593	24,244
Distributions in excess of income from, and investments in, unconsolidated affiliates	15,623	15,292
Total liabilities	1,876,833	1,744,608
Commitments and contingencies
Acadia Shareholders' Equity
Common shares, $0.001 par value, authorized 200,000,000 shares, issued and outstanding 81,557,472 and 83,708,140 shares, respectively	82	84
Additional paid-in capital	1,548,603	1,596,514
Accumulated other comprehensive income	516	2,614
Distributions in excess of accumulated earnings	(89,696)	(32,013)
Total Acadia shareholders’ equity	1,459,505	1,567,199
Noncontrolling interests	622,442	648,440
Total equity	2,081,947	2,215,639
Total liabilities and equity	$ 3,958,780	$ 3,960,247

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2018	Dec. 31, 2017
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	200,000,000
Common shares, issued (in shares)	81,557,472	83,708,140
Common shares, outstanding (in shares)	81,557,472	83,708,140

CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	12 Months Ended
CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues	$ 262,213	$ 250,262	$ 189,939
Operating expenses
Depreciation and amortization	117,549	104,934	70,011
General and administrative	34,343	33,756	40,648
Real estate taxes	36,712	35,946	25,630
Property operating	45,211	41,668	24,244
Impairment charge	0	14,455	0
Other operating	857	2,184	7,517
Total operating expenses	234,672	232,943	168,050
Operating income	27,541	17,319	21,889
Equity in earnings of unconsolidated affiliates inclusive of gain on disposition of properties of $0, $15,336 and $35,950, respectively	9,302	23,371	39,449
Interest income	13,231	29,143	25,829
Interest expense	(69,978)	(58,978)	(34,645)
Gain on change in control	0	5,571	0
(Loss) income from continuing operations before income taxes	(19,904)	16,426	52,522
Income tax (provision) benefit	(934)	(1,004)	105
(Loss) income from continuing operations before gain on disposition of properties	(20,838)	15,422	52,627
Gain on disposition of properties, net of tax	5,140	48,886	81,965
Net (loss) income	(15,698)	64,308	134,592
Net loss (income) attributable to noncontrolling interests	47,137	(2,838)	(61,816)
Net income attributable to Acadia	$ 31,439	$ 61,470	$ 72,776
Basic and diluted earnings per share (in dollars per share)	$ 0.38	$ 0.73	$ 0.94
Rental income
Revenues	$ 208,756	$ 198,941	$ 152,814
Expense reimbursements
Revenues	48,284	44,907	32,282
Other
Revenues	$ 5,173	$ 6,414	$ 4,843

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net (loss) income	$ (15,698)	$ 64,308	$ 134,592
Other comprehensive (loss) income:
Unrealized (loss) income on valuation of swap agreements	(2,659)	634	(646)
Reclassification of realized interest on swap agreements	71	3,317	4,576
Other comprehensive (loss) income	(2,588)	3,951	3,930
Comprehensive (loss) income	(18,286)	68,259	138,522
Comprehensive loss (income) attributable to noncontrolling interests	47,627	(3,377)	(62,081)
Comprehensive income attributable to Acadia	$ 29,341	$ 64,882	$ 76,441

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Shares	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Distributions in Excess of Accumulated Earnings	Total Common Shareholders’ Equity	Noncontrolling Interests
Beginning 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/distribution declared ($1.09, $1.05 and 1.16 per Common Share/OP Unit for Year Ended Dec 31, 2018, 2017 and 2016)	(97,806)				(91,053)	(91,053)	(6,753)
Employee and trustee stock compensation, net	13,694		926			926	12,768
Employee and trustee stock compensation, net (in Shares)		28,000
Windfall tax benefit	555		555			555
Change in control of previously unconsolidated investment	(75,713)						(75,713)
Acquisition of noncontrolling interest	(18,379)		7,546			7,546	(25,925)
Noncontrolling interest distributions	(80,769)						(80,769)
Noncontrolling interest contributions	295,108						295,108
Comprehensive (loss) income	138,522			3,665	72,776	76,441	62,081
Reallocation of noncontrolling interests	0		35,652			35,652	(35,652)
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		83,598,000
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
Repurchase of Common Shares (in shares)	0
Dividends/distribution declared ($1.09, $1.05 and 1.16 per Common Share/OP Unit for Year Ended Dec 31, 2018, 2017 and 2016)	$ (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
Comprehensive (loss) income	68,259			3,412	61,470	64,882	3,377
Reallocation of noncontrolling interests	0		(651)			(651)	651
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
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership	$ 0		2,068			2,068	(2,068)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership (in Shares)		117,000
Repurchase of Common Shares	$ (55,111)	$ (2)	(55,109)			(55,111)
Repurchase of Common Shares (in shares)	(2,294,235)	(2,294,000)
Dividends/distribution declared ($1.09, $1.05 and 1.16 per Common Share/OP Unit for Year Ended Dec 31, 2018, 2017 and 2016)	$ (96,010)				(89,122)	(89,122)	(6,888)
Employee and trustee stock compensation, net	12,948		574			574	12,374
Employee and trustee stock compensation, net (in Shares)		26,000
Noncontrolling interest distributions	(24,793)						(24,793)
Noncontrolling interest contributions	47,560						47,560
Comprehensive (loss) income	(18,286)			(2,098)	31,439	29,341	(47,627)
Reallocation of noncontrolling interests	0		4,556			4,556	(4,556)
Ending Balance at Dec. 31, 2018	$ 2,081,947	$ 82	$ 1,548,603	$ 516	$ (89,696)	$ 1,459,505	$ 622,442
Balance (in Shares) at Dec. 31, 2018	81,557,472	81,557,000

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
CASH FLOWS FROM OPERATING ACTIVITIES
Net (loss) income	$ (15,698)	$ 64,308	$ 134,592
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Gain on disposition of properties	(5,140)	(48,886)	(81,965)
Gain on change in control	0	(5,571)	0
Depreciation and amortization	117,549	104,934	70,011
Distributions of operating income from unconsolidated affiliates	15,556	15,556	7,256
Equity in earnings and gains of unconsolidated affiliates	(9,302)	(23,371)	(39,449)
Stock compensation expense	12,948	11,155	13,695
Amortization of financing costs	6,008	5,985	3,204
Impairment charge	0	14,455	0
Other, net	(11,768)	(10,621)	(8,095)
Changes in assets and liabilities:
Other liabilities	6,161	(4,285)	26,532
Prepaid expenses and other assets	(7,168)	(6,498)	(11,677)
Rents receivable, net	(10,044)	(11,274)	(4,847)
Accounts payable and accrued expenses	(3,026)	8,768	591
Net cash provided by operating activities	96,076	114,655	109,848
CASH FLOWS FROM INVESTING ACTIVITIES
Acquisition of real estate	(147,985)	(200,429)	(495,644)
Development, construction and property improvement costs	(94,834)	(108,142)	(149,434)
Issuance of or advances on notes receivable	(3,002)	(10,600)	(157,352)
Proceeds from the disposition of properties, net	63,866	260,711	150,378
Investments in and advances to unconsolidated affiliates	(3,161)	(6,535)	(72,098)
Return of capital from unconsolidated affiliates and other	26,338	43,684	79,030
Proceeds from notes receivable	26,000	32,000	42,819
Return of deposits for properties under contract	1,692	(2,000)	1,424
Payment of deferred leasing costs	(6,106)	(5,202)	(7,515)
Change in control of previously unconsolidated (consolidated) affiliate	573	576	(5,172)
Net cash (used in) provided by investing activities	(136,619)	4,063	(613,564)
CASH FLOWS FROM FINANCING ACTIVITIES
Principal payments on mortgage and other notes	(81,726)	(306,119)	(394,864)
Principal payments on unsecured debt	(632,300)	(277,134)	(541,790)
Proceeds received on mortgage and other notes	187,173	156,344	222,071
Proceeds from unsecured debt	648,800	359,625	666,716
(Repurchase) issuance of Common Shares	(55,111)		450,130
Capital contributions from noncontrolling interests	47,560	85,206	295,108
Distributions to noncontrolling interests	(31,568)	(39,942)	(105,994)
Dividends paid to Common Shareholders	(88,887)	(99,527)	(91,334)
Deferred financing and other costs	(4,219)	(6,211)	(11,678)
Net cash (used in) provided by financing activities	(10,278)	(127,758)	488,365
Decrease in cash and restricted cash	(50,821)	(9,040)	(15,351)
Cash of $74,823, $71,805 and $72,776 and restricted cash of $10,846, $22,904 and $37,284, respectively, beginning of year	85,669	94,709	110,060
Cash of $21,268, $74,823 and $71,805 and restricted cash of $13,580, $10,846 and $22,904, respectively, end of year	34,848	85,669	94,709
Supplemental disclosure of cash flow information
Cash paid during the period for interest, net of capitalized interest of $5,625 and $13,509 and $21,109 respectively	61,832	49,942	42,279
Cash paid for income taxes, net of refunds	1,227	875	2,036
Supplemental disclosure of non-cash investing activities
Assumption of accounts payable and accrued expenses through acquisition of real estate	2,597	2,173	3,587
Acquisition of real estate through conversion of note receivable		9,142
Acquisition of undivided interest in a property through conversion of notes receivable	22,201	60,695
Acquisition of real estate through assumption of debt			120,672
Acquisition of real estate through conversion of OP Units			29,336
Acquisition of capital lease obligation			76,461
Mortgage debt financed at time of acquisition			63,900
Assumption of prepaid expenses and other assets through acquisition of real estate			2,226
Change in control of previously unconsolidated (consolidated) investment
(Increase) decrease in real estate, net	(31,836)	(39,322)	90,559
Gain on change in control	0	5,571
Decrease in notes receivable		32,010
Decrease (increase) in investments in and advances to unconsolidated affiliates	35,881	4,159	(21,421)
Decrease in noncontrolling interest			(75,713)
Change in other assets and liabilities	(3,472)	(1,842)	1,403
Increase (decrease) in cash and restricted cash upon change of control	$ 573	$ 576	$ (5,172)

Consolidated Statements of Cashflows (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement Of Cash Flows [Abstract]
Cash and cash equivalents	$ 21,268	$ 74,823	$ 71,805
Restricted cash	13,580	10,846	22,904
Cash paid for capitalized interest	$ 5,625	$ 13,509	$ 21,109

Organization, Basis of Presentation and Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2018

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Organization, Basis of Presentation and Summary of Significant Accounting Policies

1. 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, 2018 and December 31, 2017, the Company controlled approximately 94% 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, 2018, 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 53 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 171 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 or invested in operating companies through Acadia Mervyn Investors I, LLC (“Mervyns I,” which was liquidated in 2018), 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, 2018		Unfunded Commitment		Equity Interest Held By Operating Partnership^(a)			Preferred Return			Total Distributions as of December 31, 2018 ^(b)
Fund II and Mervyns II ^(c)	6/2004		28.33	%	$	347.1	$	—		28.33	%		8	%	$	146.6
Fund III	5/2007		24.54	%		423.9		26.1		24.54	%		6	%		551.9
Fund IV	5/2012		23.12	%		420.8		109.2		23.12	%		6	%		147.4
Fund V	8/2016		20.10	%		85.1		434.9		20.10	%		6	%		—

(a)	Amount represents the current economic ownership at December 31, 2018, 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.

(c)	During April 2018, a distribution of $15.0 million was made to the Fund II investors, including $4.3 million to the Operating Partnership. This amount remains subject to re-contribution to Fund II until April 2021.

Basis of Presentation

Segments

At December 31, 2018, 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.

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.

Use of Estimates

GAAP requires the Company’s management to make estimates and assumptions that affect the amounts reported in the consolidated 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.

Reclassifications

Certain prior year amounts have been reclassified for consistency with the current year presentation in the statement of cash flows. These reclassifications had no effect on the reported results of operations.

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. When acquisitions of properties do not meet the criteria for business combinations, no goodwill is recorded and acquisition costs are capitalized.

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. Beginning January 1, 2018, gains on sale of investment properties are recognized, and the related real estate derecognized, when the Company has satisfied its performance obligations by transferring control of the property. Typically, the timing of payment and satisfaction of performance obligations occur simultaneously on the disposition date upon transfer of the property’s ownership. Prior to January 1, 2018, gains from dispositions were recognized under the full accrual or partial sales method provided that various criteria relating to terms of sales and 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. Effective January 1, 2019, these internal leasing costs will no longer be capitalized as discussed further below under ASU 2016-02.

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, 2018 and 2017, unbilled rents receivable relating to the straight-lining of rents of $47.2 million and $37.4 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, 2018 and 2017 are shown net of an allowance for doubtful accounts of $7.9 million and $5.9 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 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 allows non-corporate shareholders to deduct a portion of the Company’s dividends.

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 Adopted Accounting Pronouncements

Recently adopted accounting pronouncements include those adopted during the year ended December 31, 2018.

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 does apply to certain 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. Substantially all of the Company’s revenue is derived from its leases and therefore falls outside of the scope of this guidance. The Company implemented the standard effective January 1, 2018, using the modified retrospective approach; however, there was no cumulative effect required to be recognized in retained earnings at the date of application. With respect to its fee-derived revenue, the Company had no changes to the timing of the revenue recognition. However, the recognition of gains on dispositions of properties may be impacted prospectively in limited circumstances under which collectability may not be reasonably assured or if the Company has continuing involvement with a sold property.

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. The Company adopted ASU 2016-15 effective January 1, 2018 and elected the “cumulative distribution approach” whereby distributions received from equity method investments are classified as cash flows from operations to the extent of equity earnings and then as cash flows from investing activities thereafter. Accordingly, the Company has reclassified $6.3 million 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 year ended December 31, 2017. No such reclassification was required for the year ended December 31, 2016.

In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash. ASU 2016-18 requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, and amounts generally described as restricted cash or restricted cash equivalents. Therefore, amounts generally described as restricted cash and restricted cash equivalents should be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. The Company adopted this guidance effective January 1, 2018. Accordingly, the Company has reclassified $11.5 million and $1.9 million of its cash inflows from operating activities and $0.9 million and $9.9 million of its cash inflows from financing activities to change in cash and restricted cash in its historical presentation of cash flows 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 has been adopted by the Company effective January 1, 2018. Adoption of the new standard has reduced the number of real estate acquisitions that were accounted for as business combinations and, therefore, reduced the amount of acquisition costs that were expensed. Accordingly, the Company capitalized $0.3 million of acquisition costs during the year ended December 31, 2018 and expensed $2.1 million and $8.2 million of acquisition costs during the years ended December 31, 2017 and 2016.

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 Company adopted 2017-03 effective January 1, 2018. The adoption of ASU 2017-03 did not have a material impact on the Company’s consolidated financial statements.

In February 2017, the FASB issued ASU No. 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 Company adopted ASU 2017-05 effective January 1, 2018. The adoption of ASU 2017-05 did not have a material impact on the Company's consolidated financial statements.

In May 2017, the FASB issued ASU No. 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. The Company adopted ASU 2017-09 effective January 1, 2018. The adoption of ASU 2017-09 did not have a material impact on the Company's consolidated financial statements because the Company has not had significant modifications of its awards.

In August 2017, the FASB issued ASU No. 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 early adopted ASU 2017-12 effective January 1, 2018 and the adoption of ASU 2017-12 did not have a material impact on the Company's consolidated financial statements.

In March 2018, the FASB issued ASU No. 2018-05, Income Taxes (Topic 740): Amendments to SEC Paragraphs Pursuant to SEC Staff Accounting Bulletin No. 118, which allowed public companies to record provisional amounts in earnings for the year ended December 31, 2017 due to the complexities involved in accounting for the enactment of the Tax Cuts and Jobs Act. ASU 2018-05 was effective upon issuance. The Company recognized the estimated income tax effects of the Tax Cuts and Jobs Act in its 2017 Consolidated Financial Statements in accordance with SEC Staff Accounting Bulletin No. 118.

Recently Issued Accounting Pronouncements

Lease Accounting

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, will be capitalized and recorded on the balance sheet. For lessors, however, the accounting remains largely unchanged from the current model, with the distinction between operating, sales-type and direct-financing leases retained, but updated to align with certain changes to the lessee model and the new revenue recognition standard discussed above. Under the new guidance, contract consideration will be allocated to its lease components (such as the lease of our retail properties) and non-lease components (such as maintenance). For us as a lessor, any non-lease components will be accounted for under ASC Topic 606, Revenue from Contracts with Customers, unless the Company elects a lessor practical expedient to not separate the nonlease components from the associated lease component (see discussion below). The new guidance also includes a definition of initial direct costs that is narrower than the prior definition in current GAAP (Topic 840, Leases). This will result in a change to the accounting for our internal leasing costs, which will be expensed as incurred, as opposed to being capitalized and deferred. Commissions subsequent to successful lease execution will continue to be capitalized. ASU 2016-02 is effective for the Company beginning January 1, 2019 and will require extensive quantitative and qualitative disclosures.

ASU 2016-02 initially provided for one retrospective transition method; however, a second transition method was later added with ASU 2018-11 as described below. To ease the transition, the new lease accounting guidance permits companies to utilize certain practical expedients in their implementation of the new standard:

•

A package of three practical expedients that must be elected together for all leases and includes: (i) not reassessing expired or existing contracts as to whether they are or contain leases; (ii) not reassessing lease classification of existing leases and (iii) not reassessing the amount of capitalized initial direct costs for existing leases;

•

ASU 2016-02 also includes a practical expedient to use hindsight in determining the lease term or assessing purchase options for existing leases and in assessing impairment of right of use assets;

•

ASU 2018-01, Land Easements Practical Expedient for Transition to Topic 842 added a transition practical expedient to not reassess existing or expired land easement agreements not previously accounted for as leases; and

•

A new practical expedient under ASU 2018-11, described below.

In July 2018, the FASB issued ASU No. 2018-10, Codification Improvements to Topic 842, Leases. These amendments provide minor clarifications and corrections to ASU 2016-02, Leases (Topic 842).

In July 2018, the FASB issued ASU No. 2018-11, Leases (Topic 842): Targeted Improvements. The amendments in this Update provide entities with an additional optional transition method to adopt ASU 2016-02. Under this new transition method, an entity initially applies the new leases standard at the adoption date and recognizes a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. Consequently, an entity’s reporting under this additional transition method for the comparative periods presented in the financial statements in which it adopts the new leases standard would continue to be in accordance with current GAAP (Topic 840, Leases). The amendments in this Update also provide lessors with a practical expedient, by class of underlying asset, to make a policy election to not separate non-lease components from the associated lease component and, instead, to account for those components as a single component if the non-lease components otherwise would be accounted for under the new revenue guidance (Topic 606). Conditions are required to elect the practical expedient, and if met, the single component will be accounted for under either under Topic 842 or Topic 606 depending on which component(s) are predominant. The lessor practical expedient to not separate nonlease components from the associated component must be elected for all existing and new leases.

In December 2018, the FASB issued ASU 2018-20 Leases (Topic 842), Narrow-Scope Improvements for Lessors. This ASU modifies ASU No. 2016-02 to permit lessors, as an accounting policy election, not to evaluate whether certain sales taxes and other similar taxes are lessor costs or lessee costs. Instead, those lessors will account for those costs as if they are lessee costs. Consequently, a lessor making this election will exclude from the consideration in the contract and from variable payments not included in the consideration in the contract all collections from lessees of taxes within the scope of the election and will provide certain disclosures (includes sales, use, value added, and some excise taxes and excludes real estate taxes). The Company has elected not to evaluate whether the aforementioned costs are lessor or lessee costs. This ASU also provides that certain lessor costs require lessors to exclude from variable payments, and therefore revenue, specifically lessor costs paid by lessees directly to third parties. The amendments also require lessors to account for costs excluded from the consideration of a contract that are paid by the lessor and reimbursed by the lessee as variable payments. A lessor will record those reimbursed costs as revenue.

The Company has adopted ASU No. 2016-02 (as amended by subsequent ASUs) effective January 1, 2019 utilizing the new transition method described in ASU 2018-11 and has availed itself of all the available practical expedients described above except it will not use hindsight in determining the lease term or assessing purchase options for existing leases and in assessing impairment of right of use assets. As lessor, the Company expects that post-adoption substantially all existing leases will have no change in the timing of revenue recognition until their expiration or termination. For common area maintenance income, currently reported within expense reimbursements, while this will be considered a nonlease component within the scope of Topic 606 for new leases, the Company has elected the lessor practical expedient to not separate maintenance from the associated lease for all existing and new leases and to account for the combined component as a single lease component. The Company has determined that the effect of electing this lessor practical expedient is that revenues related to leases will be reported on one line in the presentation within the statement of income. The timing of revenue recognition is expected to be the same for the majority of the Company’s new leases as compared to similar existing leases. After adoption, the Company will no longer capitalize a significant portion of internal leasing costs that were previously capitalized (the Company capitalized $1.4 million and $1.3 million of internal leasing costs during the years ended December 31, 2018 and 2017, respectively).

As a lessee, the Company is party to several equipment, ground, and office leases with future payment obligations aggregating approximately $203.1 million at December 31, 2018. As lessee, the Company has applied the following practical expedients in the implementation ASU 2016-02: (i) to not separate non-lease components from the associated lease component as described above and (ii) to not apply the right-of-use recognition requirements to short-term leases.

Other Accounting Topics

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 February 2018, the FASB issued ASU No. 2018-02, Income Statement-Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income. These amendments provide financial statement preparers with an option to reclassify stranded tax effects within accumulated other comprehensive income to retained earnings in each period in which the effect of the change in the U.S. federal corporate income tax rate in the Tax Cuts and Jobs Act is recorded. This guidance is effective for fiscal years beginning after December 15, 2018, and interim periods therein. The Company adopted this guidance, which did not have a material effect on the Company’s financial statements, effective January 1, 2019.

In June 2018, the FASB issued ASU No. 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting. These amendments provide specific guidance for transactions for acquiring goods and services from nonemployees and specify that Topic 718 applies to all share-based payment transactions in which a grantor acquires goods or services to be used or consumed in a grantor’s own operations by issuing share-based payment awards. The amendments also clarify that Topic 718 does not apply to share-based payments used to effectively provide (i) financing to the issuer or (ii) awards granted in conjunction with selling goods or services to customers as part of a contract accounted for under Topic 606, Revenue from Contracts with Customers. This guidance is effective for fiscal years beginning after December 15, 2018, and interim periods beginning after December 15, 2020. Early adoption is permitted but not earlier than the adoption of Topic 606. The Company does not believe that this guidance will have a material effect on its consolidated financial statements as it has not historically issued share-based payments in exchange for goods or services to be consumed within its operations.

In July 2018, the FASB issued ASU No. 2018-09, Codification Improvements. These amendments provide clarifications and corrections to certain ASC subtopics including the following: 220-10 (Income Statement - Reporting Comprehensive Income - Overall), 470-50 (Debt - Modifications and Extinguishments), 480-10 (Distinguishing Liabilities from Equity - Overall), 718-740 (Compensation - Stock Compensation - Income Taxes), 805-740 (Business Combinations - Income Taxes), 815-10 (Derivatives and Hedging - Overall), and 820-10 (Fair Value Measurement - Overall). Some of the amendments in ASU 2018-09 do not require transition guidance and will be effective upon issuance; however, many of the amendments do have transition guidance with effective dates for annual periods beginning after December 15, 2018.

In August 2018, the FASB issued ASU No. 2018-13, Disclosure Framework — Changes to the Disclosure Requirements for Fair Value Measurement which removes, modifies, and adds certain disclosure requirements related to fair value measurements in ASC 820. This guidance is effective for public companies in fiscal years beginning after December 15, 2019 with early adoption permitted. The Company is currently assessing the impact this guidance will have on its consolidated financial statements.

In August 2018, the FASB issued ASU No. 2018-15 Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract to provide guidance on implementation costs incurred in a cloud computing arrangement that is a service contract. The ASU aligns the accounting for such costs with the guidance on capitalizing costs associated with developing or obtaining internal-use software. Specifically, the ASU amends ASC 350 to include in its scope implementation costs of such arrangements that are service contracts and clarifies that a customer should apply ASC 350-40 to determine which implementation costs should be capitalized. This ASU, which is effective for fiscal years beginning after December 15, 2019, is not expected to have a material impact on the Company’s financial statements as the Company has not incurred any significant costs associated with cloud computing arrangements.

In November 2018, the FASB issued ASU No. 2018-19 Codification Improvements to Topic 326, Financial Instruments – Credit Losses. This ASU modifies ASU 2016-13, which the Company expects to adopt effective January 1, 2019. The amendment clarifies that receivables arising from operating leases are not within the scope of Subtopic 326-20, Financial Instruments – Credit Losses – Measure at Amortized Cost. Instead, impairment of receivables arising from operating leases should be accounted for in accordance with Topic 842, Leases.

Real Estate

12 Months Ended

Dec. 31, 2018

Acquisition And Disposition Of Properties And Discontinued Operations [Abstract]

Real Estate

2. Real Estate

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

	December 31,
	2018			2017
Land	$	710,469		$	658,835
Buildings and improvements		2,594,828			2,406,488
Tenant improvements		151,154			131,850
Construction in progress		44,092			18,642
Properties under capital lease		76,965			76,965
Total		3,577,508			3,292,780
Less: Accumulated depreciation		(416,657	)		(339,862	)
Operating real estate, net		3,160,851			2,952,918
Real estate under development, at cost		120,297			173,702
Net investments in real estate	$	3,281,148		$	3,126,620

Acquisitions and Conversions

During the years ended December 31, 2018 and December 31, 2017, the Company acquired the following consolidated retail properties (dollars in thousands):

Property and Location	Percent Acquired	Date of Acquisition	Purchase Price
2018 Acquisitions and Conversions
Core
Bedford Green Land Parcel - Bedford Hills, NY	100%	Mar 23, 2018	$	1,337
Subtotal Core				1,337

Fund IV
Broughton Street Partners I - Savannah, GA (Conversion) (Note 4)	100%	Oct 11, 2018		36,104
Subtotal Fund IV				36,104

Fund V
Trussville Promenade - Trussville, AL	100%	Feb 21, 2018		45,259
Elk Grove Commons - Elk Grove, CA	100%	Jul 18, 2018		59,320
Hiram Pavilion - Hiram, GA	100%	Oct 23, 2018		44,443
Subtotal Fund V				149,022
Total 2018 Acquisitions and Conversions			$	186,463

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

The 2018 acquisitions were considered asset acquisitions based on accounting guidance effective as of January 1, 2018 (). The 2017 acquisitions and conversions were deemed to be business combinations. For the year ended December 31, 2018, the Company capitalized $0.3 million of acquisition costs related to the Funds. 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. No debt was assumed in any of the 2018 Acquisitions or 2017 Acquisitions or Conversions.

Revenues and net income from the Company’s consolidated 2018 acquisitions and conversions totaled $9.0 million and $0.5 million, respectively for the year ended December 31, 2018. Revenues and net loss from the Company’s consolidated 2017 acquisitions and conversions totaled $10.2 million and $3.5 million, respectively for the year ended December 31, 2017.

Purchase Price Allocations

The purchase prices for the 2018 acquisitions and the 2017 acquisitions and conversions 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, 2018 and December 31, 2017 (in thousands):

	Year Ended December 31,
	2018			2017
Net Assets Acquired
Land	$	38,086		$	48,138
Buildings and improvements		129,586			173,576
Other assets		—			84
Acquisition-related intangible assets (Note 6)		26,693			44,269
Acquisition-related intangible liabilities (Note 6)		(7,902	)		(11,535	)
Net assets acquired	$	186,463		$	254,532

Consideration
Cash	$	147,985		$	200,429
Conversion of note receivable	—				41,010
Liabilities assumed		2,597			3,363
Existing interest in previously unconsolidated investment		35,881			4,159
Change in control of previously unconsolidated investment	—				5,571
Total Consideration	$	186,463		$	254,532

Dispositions

During the years ended December 31, 2018 and December 31, 2017, the Company disposed of the following consolidated properties (in thousands):

Property and Location	Owner	Date Sold	Sale Price		Gain (Loss) on Sale
2018 Disposition
Sherman Avenue - New York, NY	Fund II	Apr 17, 2018	$	26,000	$	33
Lake Montclair - Dumfries, VA	Fund IV	Aug 27, 2018		22,450		2,923
1861 Union Street - San Francisco, CA	Fund IV	Aug 29, 2018		6,000		2,184
210 Bowery - 4 Residential Condos - New York, NY	Fund IV	Nov 30, 2018, Dec 10, 2018, Dec 17, 2018, Dec 21, 2018		12,050		—
Total 2018 Dispositions			$	66,500	$	5,140

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

The aggregate revenue, expenses and pre-tax income reported within continuing operations for the aforementioned consolidated properties that were sold during the years ended December 31, 2018, December 31, 2017 and December 31, 2016 were as follows (in thousands):

	Year Ended December 31,
	2018			2017			2016
Revenues	$	1,968		$	16,249		$	20,097
Expenses		(1,874	)		(20,529	)		(17,079	)
Loss (income) from continuing operations of disposed properties before gain on disposition of properties		94			(4,280	)		3,018
Gain on disposition of properties		5,140			48,886			81,965
Net income attributable to noncontrolling interests		(3,368	)		(32,254	)		(70,714	)
Net income attributable to Acadia	$	1,866		$	12,352		$	14,269

Properties Held for Sale

At December 31, 2018, the Company had no properties classified as 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, which was sold on April 17, 2018 as noted in the disposition table above. This property’s net operating loss of $0.5 million and $0.6 million for the year ended December 31, 2018 and 2017, respectively, is included in the table above. At December 31, 2017, the Company recognized an impairment charge of approximately $10.6 million inclusive of an amount attributable to a noncontrolling interest of $7.6 million ().

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.

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

	December 31, 2017				Year Ended 2018						December 31, 2018
	Number of Properties		Carrying Value		Transfers In		Capitalized Costs		Transfers Out		Number of Properties		Carrying Value
Core		2	$	21,897	$	—	$	6,320	$	20,458		1	$	7,759
Fund II		—		4,908		—		2,554		—		—		7,462
Fund III		2		63,939		—		36,117		78,814		1		21,242
Fund IV		1		82,958		—		876		—		1		83,834
Total		5	$	173,702	$	—	$	45,867	$	99,272		3	$	120,297

During the year ended December 31, 2018, the Company placed one Core development project into service and one Fund III development project into service. In addition to the consolidated projects noted above, the Company had one unconsolidated project in development at December 31, 2017, which it placed into service during the year ended December 31, 2018.

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, 2018

Accounts And Notes Receivable Net [Abstract]

Notes Receivable, Net

3. 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, 2018
Description	2018		2017		Number		Maturity Date	Interest Rate
Core Portfolio	$	56,475	$	101,695		2	Apr 2019 - Apr 2020	6.0% - 8.1%
Fund II		32,582		31,778		1	May 2020	2.5%
Fund III		5,306		5,106		1	Jul 2020	18.0%
Fund IV		15,250		15,250		1	Feb 2021	15.3%
	$	109,613	$	153,829		5

During the year ended December 31, 2018, the Company:

•

exchanged $22.0 million of a Core note receivable plus accrued interest thereon of $0.3 million for an additional undivided interest in the Town Center property (Note 4);

•

received full payment on $26.0 million of Core notes receivable plus accrued interest of $0.2 million;

•

funded an additional $2.8 million to its existing $15.0 million Core note receivable and entered into an agreement to extend the maturity to April 1, 2020;

•

advanced an additional $0.2 million on a Fund III note receivable; and

•

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

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;

•

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).

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, 2018

Equity Method Investments And Joint Ventures [Abstract]

Investments in and Advances to Unconsolidated Affiliates

4. 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,			December 31,
Portfolio	Property	December 31, 2018	2018			2017
Core:
	840 N. Michigan^(a)	88.43%	$	65,013		$	69,846
	Renaissance Portfolio	20%		32,458			35,041
	Gotham Plaza	49%		29,550			29,416
	Town Center^{(a, b)}	75.22%		99,758			78,801
	Georgetown Portfolio	50%		4,653			3,479
				231,432			216,583

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

Fund III:
	Fund III Other Portfolio	90%		21			167
	Self Storage Management ^(d)	95%		206			206
				227			373
Fund IV:
	Broughton Street Portfolio ^(e)	50%		3,236			48,335
	Fund IV Other Portfolio	90%		14,540			20,199
	650 Bald Hill Road	90%		12,880			13,609
				30,656			82,143

Various Funds:	Due (to) from Related Parties ^(f)			(461	)		2,415
	Other ^(g)			556			556
	Investments in and advances to unconsolidated affiliates		$	262,410		$	302,070

Core:
	Crossroads ^(h)	49%	$	15,623		$	15,292
	Distributions in excess of income from, and investments in, unconsolidated affiliates		$	15,623		$	15,292

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

(b)	During November 2017 and March 2018, as discussed below, the Company increased its ownership in Town Center.

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

(d)	Represents a variable interest entity for which the Company was determined not to be the primary beneficiary.

(e)

The Company is entitled to a 15% return on its cumulative capital contribution which was $3.0 million and $15.4 million at December 31, 2018 and December 31, 2017, respectively. In addition, the Company is entitled to a 9% preferred return on a portion of its equity, which was $2.8 million and $41.2 million at December 31, 2018 and December 31, 2017, respectively.

(f)	Represents deferred fees.

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

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

Core Portfolio

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, is being amortized over the remaining depreciable lives of the venture’s assets. The Company previously had a 22.22% interest in Town Center which then became 61.11% following the November 2017 transaction.

On March 28, 2018, the Company exchanged $22.0 million of its Brandywine Notes Receivable plus accrued interest of $0.3 million for one of the partner’s 14.11% tenancy-in-common interests in Town Center. The incremental investment in Town Center was recorded at $ 22.3 million and the excess of this amount over the venture’s book value associated with this interest, or $12.7 million, is being amortized over the remaining depreciable lives of the venture’s assets. The Company continues to apply the equity method of accounting for its aggregate 75.22% noncontrolling interest in Town Center after the March 2018 transaction.

At December 31, 2018, $38.7 million of the Brandywine Note Receivable remains outstanding (Note 3), which is collateralized by the remaining 24.78% undivided interest in Town Center.

Fund Investments

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 these investments 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, among other investments, Fund II’s cost method investment reflecting an effective 1.05% interest in Albertson’s Companies, Inc. (“Albertson’s”), a privately-held national supermarket chain. In 2017, the Company received $2.4 million in distributions from Albertson’s and reduced the carrying amount of its investment in Albertson’s to zero (Note 8), reflecting the remaining $2.0 million as equity in earnings and gains of unconsolidated affiliates in the consolidated statements of income.

Storage Post

On May 15, 2018, Fund III’s Storage Post venture, which is a cost-method investment with no carrying value, distributed $3.2 million of which the Operating Partnership’s share was $0.8 million.

Broughton Street Portfolio

During 2014, Fund IV acquired 50% interests in two joint ventures referred to as “BSP I” and “BSP II” with the same venture partner to acquire and operate a total of 23 properties in Savannah, Georgia referred to as the “Broughton Street Portfolio.” Since that time, as described below, the ventures have sold eight of the properties and terminated the master leases on two of the properties. In October 2018, the venture partner relinquished its interest in BSP I resulting in Fund IV becoming the 100% owner of the BSP I venture, which holds 11 consolidated properties at December 31, 2018 (). Fund IV accounted for this transaction as an asset purchase at fair value whereby its existing preferred and common interests were deemed consideration for the properties and no gain or loss was recognized. At December 31, 2018, the Broughton Street portfolio had 13 remaining properties, two of which are unconsolidated and are held within the BSP II venture.

2018 Dispositions of Unconsolidated Investments

On January 18, 2018, Fund IV’s Broughton Street Portfolio venture sold two properties for aggregate proceeds of $8.0 million, resulting in a net loss of $0.4 million at the property level of which the Fund’s share and the Operating Partnership’s proportionate share of the loss was zero, due to Fund IV’s preferred return.

On June 29, 2018, Fund IV’s Broughton Street Portfolio venture terminated its master leases on two of its properties resulting in a net loss of $1.0 million at the property level for which the Operating Partnership’s share was less than $0.1 million.

On August 29, 2018, Fund IV’s Broughton Street Portfolio venture sold a property for proceeds of $2.0 million, resulting in a net loss of $0.3 million at the property level, of which the Operating Partnership’s share was less than $0.1 million.

2017 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.

Fees from Unconsolidated Affiliates

The Company earned property management, construction, development, legal and leasing fees from its investments in unconsolidated partnerships totaling $1.1 million and $1.3 million and $1.2 million for the years ended December 31, 2018, 2017 and 2016, 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, $2.2 million and $2.0 million and $2.4 million for the years ended December 31, 2018, 2017 and 2016, 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,
	2018			2017
Combined and Condensed Balance Sheets
Assets:
Rental property, net	$	488,000		$	518,900
Real estate under development		—			26,681
Investment in unconsolidated affiliates		6,853			6,853
Other assets		91,497			100,901
Total assets	$	586,350		$	653,335
Liabilities and partners’ equity:
Mortgage notes payable	$	408,967		$	405,652
Other liabilities		54,675			61,932
Partners’ equity		122,708			185,751
Total liabilities and partners’ equity	$	586,350		$	653,335

Company's share of accumulated equity	$	141,384		$	185,533
Basis differential		104,084			95,358
Deferred fees, net of portion related to the Company's interest		1,780			3,472
Amounts (payable) receivable by the Company		(461	)		2,415
Investments in and advances to unconsolidated affiliates, net of Company's share of distributions in excess of income from and investments in unconsolidated affiliates		246,787			286,778
Company's share of distributions in excess of income from and investments in unconsolidated affiliates		15,623			15,292
Investments in and advances to unconsolidated affiliates	$	262,410		$	302,070

	Year Ended December 31,
	2018			2017			2016
Combined and Condensed Statements of Income
Total revenues	$	80,184		$	83,222		$	84,218
Operating and other expenses		(23,586	)		(24,711	)		(25,724	)
Interest expense		(19,954	)		(18,733	)		(16,300	)
Depreciation and amortization		(22,228	)		(24,192	)		(35,432	)
Loss on debt extinguishment		—			(154	)		—
(Loss) gain on disposition of properties		(1,673	)		18,957			(1,340	)
Net income attributable to unconsolidated affiliates	$	12,743		$	34,389		$	5,422

Company’s share of equity in net income of unconsolidated affiliates	$	12,345		$	26,039		$	40,538
Basis differential amortization		(3,043	)		(2,668	)		(1,089	)
Company’s equity in earnings of unconsolidated affiliates	$	9,302		$	23,371		$	39,449

Other Assets, Net and Accounts Payable and Other Liabilities

12 Months Ended

Dec. 31, 2018

Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]

Other Assets, Net and Accounts Payable and Other Liabilities

5. 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)	2018			2017
Other Assets, Net:
Lease intangibles, net (Note 6)	$	115,939		$	127,571
Deferred charges, net ^(a)		28,619			24,589
Prepaid expenses		18,422			16,838
Other receivables		5,058			11,356
Accrued interest receivable		17,046			11,668
Deposits		4,611			6,296
Due from seller		4,000			4,300
Deferred tax assets		2,032			2,096
Derivative financial instruments (Note 8)		7,018			4,402
Due from related parties		1,802			1,479
Corporate assets		1,953			2,369
Income taxes receivable		2,070			1,995
	$	208,570		$	214,959

(a) Deferred Charges, Net:
Deferred leasing and other costs	$	45,011		$	41,020
Deferred financing costs related to line of credit		8,960			7,786
		53,971			48,806
Accumulated amortization		(25,352	)		(24,217	)
Deferred charges, net	$	28,619		$	24,589

Accounts Payable and Other Liabilities:
Lease intangibles, net (Note 6)	$	95,045		$	104,478
Accounts payable and accrued expenses		65,215			61,420
Deferred income		34,052			31,306
Tenant security deposits, escrow and other		10,588			10,029
Derivative financial instruments (Note 8)		7,304			1,467
Income taxes payable		19			176
Other		2,738			1,176
	$	214,961		$	210,052

Lease Intangibles

12 Months Ended

Dec. 31, 2018

Goodwill And Intangible Assets Disclosure [Abstract]

Lease Intangibles

6. 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 included in other assets and other liabilities (Note 5) on the consolidated balance sheet and summarized as follows (in thousands):

	December 31, 2018									December 31, 2017
	Gross Carrying Amount			Accumulated Amortization			Net Carrying Amount			Gross Carrying Amount			Accumulated Amortization			Net Carrying Amount
Amortizable Intangible Assets
In-place lease intangible assets	$	216,021		$	(105,972	)	$	110,049		$	193,821		$	(72,749	)	$	121,072
Above-market rent		18,169			(12,279	)		5,890			16,786			(10,287	)		6,499
	$	234,190		$	(118,251	)	$	115,939		$	210,607		$	(83,036	)	$	127,571

Amortizable Intangible Liabilities
Below-market rent	$	(152,188	)	$	57,721		$	(94,467	)	$	(147,232	)	$	43,391		$	(103,841	)
Above-market ground lease		(671	)		93			(578	)		(671	)		34			(637	)
	$	(152,859	)	$	57,814		$	(95,045	)	$	(147,903	)	$	43,425		$	(104,478	)

During the year ended December 31, 2018, the Company acquired in-place lease intangible assets of $24.2 million, above-market rents of $2.5 million, and below-market rents of $7.9 million with weighted-average useful lives of 5.2, 5.1, and 20.5 years, respectively. 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, 2018 is as follows (in thousands):

Years Ending December 31,	Net Increase in Lease Revenues		Increase to Amortization			Reduction of Rent Expense		Net Income (Expense)
2019	$	8,431	$	(27,309	)	$	58	$	(18,820	)
2020		8,206		(20,511	)		58		(12,247	)
2021		7,725		(15,196	)		58		(7,413	)
2022		7,346		(10,467	)		58		(3,063	)
2023		7,053		(8,192	)		58		(1,081	)
Thereafter		49,816		(28,374	)		288		21,730
Total	$	88,577	$	(110,049	)	$	578	$	(20,894	)

Debt

12 Months Ended

Dec. 31, 2018

Debt Disclosure [Abstract]

Debt

7. Debt

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

	Interest Rate at				Carrying Value at
	December 31,	December 31,		Maturity Date at	December 31,			December 31,
	2018	2017		December 31, 2018	2018			2017
Mortgages Payable
Core Fixed Rate	3.88%-6.00%	3.88%-5.89%		Feb 2024 - Apr 2035	$	178,271		$	179,870
Core Variable Rate - Swapped ⁽^a)	3.41%-5.67%	3.41%-5.67%		Jan 2023 - Nov 2028		82,583			74,152
Total Core Mortgages Payable						260,854			254,022
Fund II Fixed Rate	1.00%-4.75%	1.00%-4.75%		May 2020 - Aug 2042		205,262			205,262
Fund II Variable Rate - Swapped ⁽^a)	4.27%	4.27%		Nov 2021		19,325			19,560
Total Fund II Mortgages Payable						224,587			224,822
Fund III Variable Rate	LIBOR+2.65%-LIBOR+4.65%	Prime+0.50%-LIBOR+4.65%		Jun 2020 - Dec 2021		90,096			65,866
Fund IV Fixed Rate	3.40%-4.50%	3.40%-4.50%		Oct 2025 - Jun 2026		8,189			10,503
Fund IV Variable Rate	LIBOR+1.60%-LIBOR+3.95%	LIBOR+1.70%-LIBOR+3.95%		Feb 2019 - Aug 2021		233,065			250,584
Fund IV Variable Rate - Swapped ⁽^a)	3.67%-4.23%	3.67%-4.23%		May 2019 - Dec 2022		71,841			86,851
Total Fund IV Mortgages Payable						313,095			347,938
Fund V Variable Rate	LIBOR+2.15%-LIBOR+2.25%	LIBOR+2.25%		Oct 2020 - Jan 2021		51,506			28,613
Fund V Variable Rate - Swapped ^(a)	4.61%-4.78%		—	Feb 2021 - Jun 2021		86,570			—
Total Fund V Mortgage Payable						138,076			28,613
Net unamortized debt issuance costs						(10,173	)		(12,943	)
Unamortized premium						753			856
Total Mortgages Payable					$	1,017,288		$	909,174
Unsecured Notes Payable
Core Term Loans	LIBOR+1.25%		—	Mar 2023	$	383		$	—
Core Variable Rate Unsecured Term Loans - Swapped ^(a)	2.49%-4.05%	2.54%-3.59%		Mar 2023		349,617			300,000
Total Core Unsecured Notes Payable						350,000			300,000
Fund II Unsecured Notes Payable	LIBOR+1.65%	LIBOR+1.40%		Sep 2020		40,000			31,500
Fund IV Term Loan/Subscription Facility	LIBOR+1.65%-LIBOR+2.75%	LIBOR+1.65%-LIBOR+2.75%		Oct 2019 - Dec 2019		40,825			40,825
Fund V Subscription Facility	LIBOR+1.60%	LIBOR+1.60%		May 2020		102,800			103,300

Net unamortized debt issuance costs						(368	)		(1,890	)
Total Unsecured Notes Payable					$	533,257		$	473,735
Unsecured Line of Credit
Core Unsecured Line of Credit	LIBOR+1.35%	LIBOR+1.40%		Mar 2022	$	—		$	18,048
Core Unsecured Line of Credit - Swapped ^(a)	4.15%-5.02%	4.20%-5.07%		Mar 2022		—			23,452
Total Unsecured Line of Credit					$	—		$	41,500

Total Debt - Fixed Rate ^(b)					$	1,001,658		$	899,650
Total Debt - Variable Rate ^(c)						558,675			538,736
Total Debt						1,560,333			1,438,386
Net unamortized debt issuance costs						(10,541	)		(14,833	)
Unamortized premium						753			856
Total Indebtedness					$	1,550,545		$	1,424,409

(a)

At December 31, 2018, the stated rates ranged from LIBOR + 1.70% to LIBOR +1.90% for Core variable-rate debt; LIBOR + 1.39% for Fund II variable-rate debt; LIBOR + 2.65% to LIBOR + 4.65% for Fund III variable-rate debt; LIBOR + 1.60% to LIBOR +3.95% for Fund IV variable-rate debt; LIBOR + 2.15% to LIBOR + 2.25% for Fund V variable-rate debt; LIBOR + 1.25% for Core variable-rate unsecured term loans; and LIBOR + 1.35% for Core variable-rate unsecured lines of credit.

(b)	Includes $609.9 million and $504.0 million, respectively, of variable-rate debt that has been fixed with interest rate swap agreements as of the periods presented.

(c)	Includes $143.8 million and $141.1 million, respectively, of variable-rate debt that is subject to interest cap agreements.

Credit Facility

On February 20, 2018, the Company entered into a $500.0 million senior unsecured credit facility (the “Credit Facility”), comprised of a $150.0 million senior unsecured revolving credit facility (the “Revolver”) which bears interest at LIBOR + 1.35%, and a $350.0 million senior unsecured term loan (the “Term Loan”) which bears interest at LIBOR + 1.25%. 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 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.

Mortgages Payable

During the year ended December 31, 2018, the Company obtained four new Fund V mortgages totaling $109.5 million with a weighted-average interest rate of LIBOR + 1.99% collateralized by four properties and maturing in 2021. In addition, the Company obtained a $73.5 million Core mortgage with an interest rate of LIBOR + 1.50% collateralized by one property and maturing in 2028. As of December 31, 2018, the Company had drawn $50.0 million on this loan. The Company entered into interest rate swap contracts to effectively fix the variable portion of the interest rates of four of these obligations with a notional value of $136.6 million at an interest rate of 2.86%. In addition, the Company drew down $24.6 million on a Fund III construction loan. During the year ended December 31, 2018, the Company repaid one Core mortgage in full, which had a balance of $40.4 million and an interest rate of LIBOR + 1.65%, and three Fund IV mortgages in full, totaling $27.2 million with a weighted-average interest rate of LIBOR + 2.81%. The Company also made scheduled principal payments of $6.7 million during the year. At December 31, 2018 and December 31, 2017, the Company’s mortgages were collateralized by 43 and 42 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, which was originated in June 2006 and had an original principal amount of $26.3 million, was in default and subject to litigation at December 31, 2018 and December 31, 2017. This loan bears interest at 6.00%, excluding default interest of 5%, and is collateralized by a property, in which the Company holds a 22% controlling interest. 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. The Company believes it has valid defenses and intends to vigorously defend itself.

Unsecured Notes Payable

Unsecured notes payable for which total availability was $62.3 million and $70.3 million at December 31, 2018 and December 31, 2017, respectively, are comprised of the following:

•

As discussed above, the Core unsecured term loans totaling $300.0 million were refinanced in February 2018, into one $350.0 million term loan with an interest rate of LIBOR+ 1.25% and maturing in March 2023. The outstanding balance of the Core term loans was $350.0 million and $300.0 million, respectively, at December 31, 2018 and December 31, 2017. During the year ended December 31, 2018, the Company entered into an interest rate swap contract to effectively fix the variable portion of the interest rate with a notional value of $50.0 million at an interest rate of 2.80%. The Company previously entered into swap agreements fixing the rates of the remaining Core term loans.

•

Fund II has a $40.0 million term loan secured by the real estate assets of City Point Phase II and guaranteed by the Company and the Operating Partnership. The outstanding balance of the Fund II term loan was $40.0 million and $31.5 million at December 31, 2018 and December 31, 2017, respectively. Total availability was $0.0 and $8.5 million at December 31, 2018 and December 31, 2017, respectively.

•

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 at each of December 31, 2018 and December 31, 2017. Total availability was $1.0 million at each of December 31, 2018 and December 31, 2017. The outstanding balance of the Fund IV subscription line was $0.0 million and total available credit was $14.1 million at each of December 31, 2018 and December 31, 2017, reflecting letters of credit of $7.4 million.

•

Fund V has a $150.0 million subscription line collateralized by Fund V’s unfunded capital commitments and guaranteed by the Operating Partnership. The outstanding balance and total available credit of the Fund V subscription line was $102.8 million and $47.2 million, respectively at December 31, 2018. 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 Revolving Line of Credit

As discussed above, the Core unsecured revolving line of credit was refinanced in February 2018. The Company had a total of $137.7 million and $96.2 million, respectively, available under its $150.0 million Core unsecured revolving lines of credit reflecting borrowings of $0.0 and $41.5 million, respectively, and letters of credit of $12.3 million at each of December 31, 2018 and December 31, 2017. At December 31, 2017, a portion of the Core unsecured revolving line of credit was swapped to a fixed rate.

Scheduled Debt Principal Payments

The scheduled principal repayments of the Company’s consolidated indebtedness, as of December 31, 2018 are as follows (in thousands):

Year Ending December 31,
2019	$	219,118
2020		527,304
2021		180,511
2022		48,528
2023		370,680
Thereafter		214,192
		1,560,333
Unamortized premium		753
Net unamortized debt issuance costs		(10,541	)
Total indebtedness	$	1,550,545

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

Financial Instruments and Fair Value Measurements

12 Months Ended

Dec. 31, 2018

Fair Value Disclosures [Abstract]

Financial Instruments and Fair Value Measurements

8. 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 year ended December 31, 2018 or 2017.

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, 2018						December 31, 2017
	Level 1		Level 2		Level 3		Level 1		Level 2		Level 3
Assets
Money Market Funds	$	4,504	$	—	$	—	$	3	$	—	$	—
Derivative financial instruments		—		7,018		—		—		4,402		—
Liabilities
Derivative financial instruments		—		7,304		—		—		1,467		—

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)

The Company did not record any impairment charges during the year ended December 31, 2018. 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 a property 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. This property was sold in April 2018. These fair value measurements approximated the estimated selling prices less estimated costs to sell.

Derivative Financial Instruments

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

					Strike Rate								Fair Value
Derivative Instrument	Aggregate Notional Amount		Effective Date	Maturity Date	Low				High			Balance Sheet Location	December 31, 2018			December 31, 2017
Core
Interest Rate Swaps	$	111,117	Dec 2012 - Jul 2020	Dec 2022 - Jul 2030		2.80	%	—		3.77	%	Other Liabilities ^(a)	$	(6,332	)	$	(1,438	)
Interest Rate Swaps		321,083	Feb 2013 - Dec 2017	Nov 2019 - Jul 2027		1.24	%	—		3.77	%	Other Assets		6,022			4,076
	$	432,200											$	(310	)	$	2,638

Fund II
Interest Rate Swap	$	19,325	Oct 2014	Nov 2021		2.88	%	—		2.88	%	Other Assets	$	108		$	—
Interest Rate Swap		—	Oct 2014	Nov 2021		2.88	%	—		2.88	%	Other Liabilities		—			(29	)
	$	19,325											$	108		$	(29	)

Fund III
Interest Rate Cap	$	58,000	Dec 2016	Jan 2020		3.00	%	—		3.00	%	Other Assets	$	8		$	14

Fund IV
Interest Rate Swaps	$	71,841	Mar 2017 - Nov 2017	Mar 2020 - Dec 2022		1.82	%	—		2.11	%	Other Assets	$	851		$	295
Interest Rate Caps		108,900	July 2016 - Nov 2016	Aug 2019 - Dec 2019		3.00	%	—		3.00	%	Other Assets		8			17
	$	180,741											$	859		$	312

Fund V
Interest Rate Swap	$	16,900	Jan 2018	Feb 2021		2.41	%	—		2.41	%	Other Assets	$	21		$	—
Interest Rate Swaps		69,670	Jun 2018	Jun 2021 - Jun 2023		2.78	%	—		2.88	%	Other Liabilities		(972	)		—
	$	86,570											$	(951	)	$	—

Total asset derivatives													$	7,018		$	4,402
Total liability derivatives													$	(7,304	)	$	(1,467	)

(a)

Includes two swaps with a fair value of ($2.9) million which were acquired during July 2018 and are not effective until July 2020.

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 $2.3 million included in accumulated other comprehensive (loss) income related to derivatives will be reclassified to interest expense within the next twelve months. As of December 31, 2018 and December 31, 2017, 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,
	2018			2017		2016
Amount of (loss) income recognized in other comprehensive income	$	(2,659	)	$	634	$	(646	)
Amount of loss subsequently reclassified to earnings		71			3,317		4,576

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, inclusive of amounts attributable to noncontrolling interests where applicable):

			December 31, 2018				December 31, 2017
	Level		Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
Notes Receivable ^(a)		3	$	109,613	$	107,370	$	153,829	$	151,712
Mortgage and Other Notes Payable ^(a)		3		1,026,708		1,021,075		921,261		921,891
Investment in non-traded equity securities ^(b)		3		—		23,208		—		22,824
Unsecured notes payable and Unsecured line of credit ^(c)		2		533,625		533,954		517,125		515,330

(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, 2018.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2018

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

9. 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 $55.5 million and $98.7 million as of December 31, 2018 and December 31, 2017, respectively.

At each of December 31, 2018 and December 31, 2017, the Company had letters of credit outstanding of $19.7 million. 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, 2018

Stockholders Equity Including Portion Attributable To Noncontrolling Interest [Abstract]

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income

10. Shareholders’ Equity, Noncontrolling Interests and Other Comprehensive Income

Common Shares and Units

The Company completed the following transactions in its common shares during the year ended December 31, 2018:

•

The Company withheld 3,288 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).

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.

Share Repurchases

During 2018, the Company revised its share repurchase program. The new share repurchase program authorizes management, at its discretion, to repurchase up to $200.0 million of its outstanding Common Shares. The program may be discontinued or extended at any time. The Company repurchased 2,294,235 shares for $55.1 million, inclusive of $0.1 million of fees, during the year ended December 31, 2018. The Company did not repurchase any shares during the year ended December 31, 2017. As of December 31, 2018, management may repurchase up to approximately $144.9 million of the Company’s outstanding Common Shares under this program.

Dividends and Distributions

On November 13, 2018, the Board of Trustees declared an increase of $0.01 to the $0.28 per Common Share regular quarterly cash dividend, which was paid on January 15, 2019 to holders of record as of December 31, 2018.

On August 7, 2018, the Board of Trustees declared a regular quarterly cash dividend of $0.27 per Common Share, which was paid on October 15, 2018 to the holders of record as of September 28, 2018.

On May 11, 2018, the Board of Trustees declared a regular quarterly cash dividend of $0.27 per Common Share, which was paid on July 13, 2018 to holders of record as of June 29, 2018.

On February 27, 2018, the Board of Trustees declared a regular quarterly cash dividend of $0.27 per Common Share, which was paid on April 13, 2018 to holders of record as of March 30, 2018.

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.

Accumulated Other Comprehensive Income

The following table sets forth the activity in accumulated other comprehensive income for the years ended December 31, 2018, 2017 and 2016 (in thousands):

	Gains or Losses on Derivative Instruments
Balance at January 1, 2018	$	2,614

Other comprehensive loss before reclassifications		(2,659	)
Reclassification of realized interest on swap agreements		71
Net current period other comprehensive loss		(2,588	)
Net current period other comprehensive loss attributable to noncontrolling interests		490
Balance at December 31, 2018	$	516

Balance at January 1, 2017	$	(798	)

Other comprehensive income before reclassifications		634
Reclassification of realized interest on swap agreements		3,317
Net current period other comprehensive income		3,951
Net current period other comprehensive income 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 income		3,930
Net current period other comprehensive income 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 years ended December 31, 2018, 2017 and 2016 (dollars in thousands):

	Noncontrolling Interests in Operating Partnership ^(a)			Noncontrolling Interests in Partially-Owned Affiliates ^(b)			Total
Balance at January 1, 2018	$	102,921		$	545,519		$	648,440
Distributions declared of $1.09 per Common OP Unit		(6,888	)		—			(6,888	)
Net income (loss) for the year ended December 31, 2018		2,572			(49,709	)		(47,137	)
Conversion of 117,978 Common OP Units to Common Shares by limited partners of the Operating Partnership		(2,068	)		—			(2,068	)
Other comprehensive loss - unrealized loss on valuation of swap agreements		(129	)		(681	)		(810	)
Reclassification of realized interest expense on swap agreements		(3	)		323			320
Noncontrolling interest contributions		—			47,560			47,560
Noncontrolling interest distributions		—			(24,793	)		(24,793	)
Employee Long-term Incentive Plan Unit Awards		12,374			—			12,374
Rebalancing adjustment ^(c)		(4,556	)		—			(4,556	)
Balance at December 31, 2018	$	104,223		$	518,219		$	622,442

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 year ended December 31, 2017		4,159			(1,321	)		2,838
Conversion of 81,453 Common OP Units and 5,000 Preferred OP Units to Common Shares by limited partners of the Operating Partnership		(1,541	)		—			(1,541	)
Other comprehensive income (loss) - unrealized gain (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 ^(c)		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 year ended 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		—			(25,925	)		(25,925	)
Other comprehensive loss - 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 ^(c)		(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’ 3,329,640, 3,328,873 and 3,308,875 Common OP Units at December 31, 2018, 2017 and 2016, respectively; (ii) 188 Series A Preferred OP Units at December 31, 2018, 2017 and 2016; (iii) 136,593 Series C Preferred OP Units at December 31, 2018, 2017 and 2016; and (iv) 2,569,044, 2,274,147 and 1,997,099 LTIP units at December 31, 2018, 2017 and 2016, respectively, as discussed in Share Incentive Plan (). Distributions declared for Preferred OP Units are reflected in net income (loss) 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)	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 during the year ended December 31, 2018.

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, 2018, 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 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. Through December 31, 2018, 5,000 Series C Preferred OP Units were converted into 17,165 Common OP Units and then into Common Shares.

Leases

12 Months Ended

Dec. 31, 2018

Leases [Abstract]

Leases

11. 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 sixty years and generally provide for additional rents based on certain operating expenses as well as tenants’ sales volumes.

The Company leases land at six of its shopping centers, which are accounted for as operating leases and generally provide the Company with renewal options. Ground rent expense was $1.7 million, $1.4 million and $1.2 million (including capitalized ground rent at a property under development of $0, $0.1 million and $0.6 million) for the years ended December 31, 2018, 2017 and 2016 respectively. The leases terminate at various dates between 2020 and 2066. These leases provide the Company with options to renew for additional terms aggregating up to 22 years. The Company also leases space for its corporate office. Office rent expense under these leases was $1.0 million for each of the years ended December 31, 2018, 2017 and 2016, respectively.

Capital Lease

During 2016, the Company entered into a 49-year master lease, which is accounted for as a capital lease. During the years ended December 31, 2018, 2017 and 2016, payments for this lease totaled $2.5 million, $2.5 million and $1.3 million, respectively. 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 non-cancelable tenant leases greater than one year (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, land and equipment, as of December 31, 2018, are summarized as follows (in thousands):

Year Ending December 31,	Minimum Rental Revenues		Minimum Rental Payments
2019	$	187,158	$	4,775
2020		178,691		4,571
2021		159,749		4,354
2022		139,294		4,404
2023		121,456		4,425
Thereafter		513,853		180,618
Total	$	1,300,201	$	203,147

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 2020.

During the years ended December 31, 2018, 2017 and 2016, no single tenant collectively comprised more than 10% of the Company’s consolidated total revenues.

Segment Reporting

12 Months Ended

Dec. 31, 2018

Segment Reporting [Abstract]

Segment Reporting

12. 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, 2018
	Core Portfolio			Funds			Structured Financing		Unallocated			Total
Revenues	$	167,894		$	94,319		$	—	$	—		$	262,213
Depreciation and amortization		(60,903	)		(56,646	)		—		—			(117,549	)
Property operating expenses, other operating and real estate taxes		(45,138	)		(37,642	)		—		—			(82,780	)
General and administrative expenses		—			—			—		(34,343	)		(34,343	)
Operating income		61,853			31			—		(34,343	)		27,541
Gain on disposition of properties		—			5,140			—		—			5,140
Interest income		—			—			13,231		—			13,231
Equity in earnings of unconsolidated affiliates inclusive of gains on disposition of properties ^(a)		7,415			1,887			—		—			9,302
Interest expense		(27,575	)		(42,403	)		—		—			(69,978	)
Income tax provision		—			—			—		(934	)		(934	)
Net income		41,693			(35,345	)		13,231		(35,277	)		(15,698	)
Net loss attributable to noncontrolling interests		752			46,385			—		—			47,137
Net income attributable to Acadia	$	42,445		$	11,040		$	13,231	$	(35,277	)	$	31,439

Real estate at cost	$	2,069,439		$	1,628,366		$	—	$	—		$	3,697,805
Total assets	$	2,232,695		$	1,616,472		$	109,613	$	—		$	3,958,780
Cash paid for acquisition of real estate	$	1,343		$	146,642		$	—	$	—		$	147,985
Cash paid for development and property improvement costs	$	32,662		$	62,172		$	—	$	—		$	94,834

	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	)
General and administrative expenses		—			—			—		(33,756	)		(33,756	)
Impairment charge		—			(14,455	)		—		—			(14,455	)
Operating income (loss)		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 ^(a)		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	$	42,026		$	66,116		$	—	$	—		$	108,142

	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 ^(a)		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

(a)

Equity in earnings of unconsolidated affiliates for the Core segment includes $5.8 million, $1.9 million and $0.9 million related to one unconsolidated affiliate, Town Center, for the years ended December 31, 2018, 2017 and 2016, respectively. During 2017 and 2018, the Company increased its ownership in its Town Center investment from 22.22% to 75.22% (). Effective in 2018, the Company consolidated a property association entity that incurs all property-related costs associated with Town Center. Such costs aggregated $0.7 million for the year ended December 31, 2018 and are included in depreciation and amortization and property operating expenses other operating and real estate taxes within the Core segment.

Share Incentive and Other Compensation

12 Months Ended

Dec. 31, 2018

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Share Incentive and Other Compensation

13. 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, 2018 a total of 1,176,340 shares remained available to be issued under the Share Incentive Plan.

Restricted Shares and LTIP Units

During the year ended December 31, 2018, the Company issued 381,821 LTIP Units and 5,767 Restricted Share Units to employees of the Company pursuant to the Share Incentive Plan. The fair value of the Restricted Share Units and LTIP Units as of the grant date was $10.4 million. Certain of these equity awards were granted in performance-based Restricted Share Units or LTIP Units to market conditions as described below (“2018 Performance Shares”). These awards were measured at their fair value on the grant date, incorporating the following factors:

•

A portion of these annual equity award is granted in performance-based Restricted Share Units or LTIP Units that may be earned based on the Company’s attainment of specified relative total shareholder returns (“Relative TSR”) hurdles.

•

In the event the Relative TSR percentile falls between the 25th percentile and the 50th percentile, Relative TSR vesting percentage is determined using a straight-line linear interpolation between 50% and 100% and in the event that the Relative TSR percentile falls between the 50th percentile and 75th percentile, the Relative TSR vesting percentage is determined using a straight-line linear interpolation between 100% and 200%.

•

Two-thirds (2/3) of the performance-based LTIP Units will vest based on the Company’s total shareholder return (“TSR”) for the three -year forward-looking performance period ending December 31, 2020 relative to the constituents of the SNL U.S. REIT Retail Shopping Center Index and one-third (1/3) on the Company’s TSR for the three-year forward-looking performance period as compared to the constituents of the SNL U.S. REIT Retail Index (both on a non-weighted basis).

•

If the Company’s performance fails to achieve the aforementioned hurdles at the culmination of the three-year performance period, all performance-based shares will be forfeited. Any earned performance-based shares vest 60% at the end of the performance period, with the remaining 40% of shares vesting ratably over the next two years.

For valuation of the 2018 Performance Shares, a Monte Carlo simulation was used to estimate the fair values based on probability of satisfying the market conditions and the projected share prices at the time of payments, discounted to the valuation dates over the three-year performance periods. The assumptions include volatility (18.0%) and risk-free interest rates (2.4%).

Total long-term incentive compensation expense, including the expense related to the Share Incentive Plan, was $8.4 million each for the years ended December 31, 2018 and 2017, respectively and is recorded in General and Administrative in the Consolidated Statements of Income.

In addition, during the quarter ended December 31, 2018, in connection with the retirement of an executive, an additional 26,632 LTIP Units were issued. The value of these LTIP Units was $0.6 million and was recognized as compensation expense in 2018. Also, in connection with this retirement, the Company recognized $1.7 million as compensation expense relating to the acceleration of previously granted LTIP Units.

In addition, members of the Board of Trustees (the “Board”) have been issued shares and units under the Share Incentive Plan. During 2018, the Company issued 17,427 LTIP Units and 17,050 Restricted Shares to Trustees of the Company in connection with Trustee fees. Vesting with respect to 8,949 of the LTIP Units and 5,181 of the Restricted Shares will be on the first anniversary of the date of issuance and 8,478 of the LTIP Units and 11,869 of the Restricted Shares 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 $1.3 million and $1.2 million for the years ended December 31, 2018 and 2017, 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 22.8% 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, 2018.

Compensation expense of $0 and $0.6 million was recognized for the year ended December 31, 2018 and 2017, 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
Granted		22,817			23.65		425,880			26.80
Vested		(25,261	)		30.79		(431,827	)		29.72
Forfeited		(428	)		27.25		(12,266	)		28.57
Unvested at December 31, 2018		38,455		$	22.44		891,886		$	26.87

The weighted-average grant date fair value for Restricted Shares and LTIP Units granted for the years ended December 31, 2018 and 2017 were $26.64 and $31.69, respectively. As of December 31, 2018, there was $14.1 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 1.6 years. The total fair value of Restricted Shares that vested for the years ended December 31, 2018 and 2017, was $0.8 million and $0.7 million, respectively. The total fair value of LTIP Units that vested during the years ended December 31, 2018 and 2017, was $12.8 million and $7.3 million, respectively.

Other Plans

On a combined basis, the Company incurred a total of $0.3 million, $0.2 million and $0.2 million related to the following employee benefit plans for each of the years ended December 31, 2018, 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. A total of 3,495 and 4,514 Common Shares were purchased by employees under the Purchase Plan for the year ended December 31, 2018 and 2017, respectively.

Deferred Share Plan

During 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 $18,500, for the year ended December 31, 2018.

Federal Income Taxes

12 Months Ended

Dec. 31, 2018

Income Tax Disclosure [Abstract]

Federal Income Taxes

14. 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, 2018, 2017 and 2016, 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. 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, 2018, the Company recognized no material adjustments regarding its tax accounting treatment for uncertain tax provisions. As of December 31, 2018, the tax years that remain subject to examination by the major tax jurisdictions under applicable statutes of limitations are generally the year 2015 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)	2018			2017			2016
Net income attributable to Acadia	$	31,439		$	61,470		$	72,776
Deferred cancellation of indebtedness income		2,050			2,050			2,050
Deferred rental and other income ^(a)		1,222			(934	)		1,610
Book/tax difference - depreciation and amortization ^(a)		23,166			21,334			15,189
Straight-line rent and above- and below-market rent adjustments ^(a)		(12,129	)		(10,559	)		(7,882	)
Book/tax differences - equity-based compensation		6,042			5,325			10,307
Joint venture equity in earnings, net ^(a)		13,905			9,114			(2,011	)
Impairment charges and reserves		—			—			769
Acquisition costs ^(a)		326			1,135			5,116
Gains		—			(5,181	)		—
Book/tax differences - miscellaneous		(2,821	)		930			(4,924	)
Taxable income	$	63,200		$	84,684		$	93,000
Distributions declared	$	89,122		$	87,848		$	91,053

(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,
	2018					2017					2016
	Per Share		%			Per Share		%			Per Share		%
Ordinary income - Non-Section 199A		—		—	%	$	0.82		78	%	$	0.77		66	%
Ordinary income - Section 199A	$	0.87		100	%		—		—	%		—		—	%
Qualified dividend		—		—	%		—		—	%		—		—	%
Capital gain		—		—	%		0.23		22	%		0.39		34	%
Total ^(b)	$	0.87		100	%	$	1.05		100	%	$	1.16		100	%

(b)	The fourth quarter 2018 regular dividend was $0.28 per common share of which approximately $0.06 was allocable to 2018 and approximately $0.22 is allocable to 2019.

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,
	2018			2017			2016
TRS loss before income taxes	$	(2,609	)	$	(3,604	)	$	(1,583	)
(Provision) benefit for income taxes:
Federal		(377	)		(982	)		378
State and local		26			423			97
TRS net loss before noncontrolling interests		(2,960	)		(4,163	)		(1,108	)
Noncontrolling interests		4			8			(9	)
TRS net loss	$	(2,956	)	$	(4,155	)	$	(1,117	)

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,
	2018			2017			2016
Federal tax benefit at statutory tax rate	$	(548	)	$	(1,225	)	$	(538	)
TRS state and local taxes, net of Federal benefit		(165	)		(190	)		(84	)
Tax effect of:
Permanent differences, net		951			1,131			1,663
Prior year over-accrual, net		—			(1,541	)		—
Effect of Tax Cuts and Jobs Act		—			1,982			—
Other		172			404			(1,516	)
REIT state and local income and franchise taxes		524			443			370
Total provision (benefit) for income taxes	$	934		$	1,004		$	(105	)

As of December 31, 2018, and 2017, 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 $0 and $1.0 million, capital loss carryovers of $0.1 million and $0 and net operating loss carryovers of $2.0 million and $1.1 million, respectively.

Earnings Per Common Share

12 Months Ended

Dec. 31, 2018

Earnings Per Share [Abstract]

Earnings Per Common Share

15. 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 (Note 10). 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”) 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)	2018			2017			2016
Numerator:
Net income attributable to Acadia	$	31,439		$	61,470		$	72,776
Less: net income attributable to participating securities		(267	)		(642	)		(793	)
Income from continuing operations net of income attributable to participating securities	$	31,172		$	60,828		$	71,983

Denominator:
Weighted average shares for basic earnings per share		82,080,159			83,682,789			76,231,000
Effect of dilutive securities:
Employee unvested restricted shares		—			2,682			12,550
Denominator for diluted earnings per share		82,080,159			83,685,471			76,243,550

Basic and diluted earnings per Common Share from continuing operations attributable to Acadia	$	0.38		$	0.73		$	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			136,593			141,593
Series C Preferred OP Units - Common share equivalent		474,278			479,978			410,207
Restricted shares		36,879			41,299			50,156

Summary of Quarterly Financial Information (Unaudited)

12 Months Ended

Dec. 31, 2018

Quarterly Financial Information Disclosure [Abstract]

Summary of Quarterly Financial Information (Unaudited)

16. Summary of Quarterly Financial Information (Unaudited)

The quarterly results of operations of the Company for the years ended December 31, 2018 and 2017 are as follows (in thousands, except per share amounts):

	Three Months Ended ^(a)
	March 31, 2018			June 30, 2018			September 30, 2018			December 31, 2018
Revenues	$	63,124		$	63,569		$	66,075		$	69,445
Net loss		(4,160	)		(2,270	)		(2,597	)		(6,671	)
Net loss attributable to noncontrolling interests		11,579			9,935			11,822			13,801
Net income attributable to Acadia		7,419			7,665			9,225			7,130

Earnings per share attributable to Acadia:
Basic	$	0.09		$	0.09		$	0.11		$	0.09
Diluted		0.09			0.09			0.11			0.09

Weighted average number of shares:
Basic		83,434			81,756			81,566			81,591
Diluted		83,438			81,756			81,566			81,591

Cash dividends declared per Common Share	$	0.27		$	0.27		$	0.27		$	0.28

(a)	The three months ended September 30, 2018 includes an aggregate $5.1 million gain on the sales of two consolidated Fund IV properties (), of which $3.9 million was attributable to noncontrolling interests.

	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
Diluted	$	0.18		$	0.14	$	0.15		$	0.25
		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 ().

(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).

Subsequent Events

12 Months Ended

Dec. 31, 2018

Subsequent Events [Abstract]

Subsequent Events

17. Subsequent Events

Capital Called

Effective January 9, 2019, Fund V called capital of $33.2 million of which the Company’s share was $6.7 million.

Financing and Hedging Transactions

On January 4, 2019, the Company entered into $100.0 million notional amounts of 10-year interest rate swaps at a fixed rate of approximately 2.6%.

On January 11, 2019, Fund V obtained a mortgage for its Elk Grove Commons property in the amount of $41.5 million, and also entered into a swap to fix the rate.

Acquisition and Disposition

On January 23, 2019, Fund III sold its 3104 M Street property for $10.5 million to an unconsolidated venture in which the Company holds a 20% interest, referred to as the Renaissance Portfolio (). In addition, the Renaissance Portfolio venture assumed the related Fund III mortgage of $4.7 million.

SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS

12 Months Ended

Dec. 31, 2018

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, 2018:
Allowance for deferred tax asset	$	1,530	$	—	$	—		$	(1,530	)	$	—
Allowance for uncollectible accounts		5,920		2,532		(531	)		—			7,921
Allowance for notes receivable		—		—		—			—			—
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		—		—		—			—			—

SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION

12 Months Ended

Dec. 31, 2018

Real Estate And Accumulated Depreciation Disclosure [Abstract]

Schedule III - Real Estate and Accumulated Depreciation

ACADIA REALTY TRUST

SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION

December 31, 2018

				Initial Cost to Company						Amount at Which Carried at December 31, 2018
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	$	3,222	$	1,147	$	10,647	$	11,794	$	8,112	1993	(a)	40 years
New Loudon Center Latham, NY		—			505		4,161		13,965		505		18,126		18,631		14,890	1993	(a)	40 years
Mark Plaza Edwardsville, PA		—			—		3,396		—		—		3,396		3,396		2,981	1993	(c)	40 years
Plaza 422 Lebanon, PA		—			190		3,004		2,809		190		5,813		6,003		5,227	1993	(c)	40 years
Route 6 Mall Honesdale, PA		—			1,664		—		12,490		1,664		12,490		14,154		9,813	1994	(c)	40 years
Abington Towne Center Abington, PA		—			799		3,197		2,876		799		6,073		6,872		4,016	1998	(a)	40 years
Bloomfield Town Square Bloomfield Hills, MI		—			3,207		13,774		25,803		3,207		39,577		42,784		23,366	1998	(a)	40 years
Elmwood Park Shopping Center Elmwood Park, NJ		—			3,248		12,992		15,738		3,798		28,180		31,978		19,867	1998	(a)	40 years
Merrillville Plaza Hobart, IN		—			4,288		17,152		5,726		4,288		22,878		27,166		13,173	1998	(a)	40 years
Marketplace of Absecon Absecon, NJ		—			2,573		10,294		4,920		2,577		15,210		17,787		8,603	1998	(a)	40 years
239 Greenwich Avenue Greenwich, CT		27,000			1,817		15,846		1,086		1,817		16,932		18,749		8,285	1998	(a)	40 years
Hobson West Plaza Naperville, IL		—			1,793		7,172		4,069		1,793		11,241		13,034		5,431	1998	(a)	40 years
Village Commons Shopping Center Smithtown, NY		—			3,229		12,917		4,597		3,229		17,514		20,743		9,918	1998	(a)	40 years
Town Line Plaza Rocky Hill, CT		—			878		3,510		7,736		907		11,217		12,124		9,206	1998	(a)	40 years
Branch Shopping Center Smithtown, NY		—			3,156		12,545		16,119		3,401		28,419		31,820		12,757	1998	(a)	40 years
Methuen Shopping Center Methuen, MA		—			956		3,826		1,484		961		5,305		6,266		2,683	1998	(a)	40 years
The Gateway Shopping Center South Burlington, VT		—			1,273		5,091		12,413		1,273		17,504		18,777		10,169	1999	(a)	40 years
Mad River Station Dayton, OH		—			2,350		9,404		2,173		2,350		11,577		13,927		5,955	1999	(a)	40 years
Pacesetter Park Shopping Center Ramapo, NY		—			1,475		5,899		3,743		1,475		9,642		11,117		5,439	1999	(a)	40 years
Brandywine Holdings Wilmington, DE		26,250			5,063		15,252		2,495		5,201		17,609		22,810		7,199	2003	(a)	40 years
Bartow Avenue Bronx, NY		—			1,691		5,803		1,190		1,691		6,993		8,684		3,250	2005	(c)	40 years
Amboy Road Staten Island, NY		—			—		11,909		2,632		—		14,541		14,541		7,319	2005	(a)	40 years
Chestnut Hill Philadelphia, PA		—			8,289		5,691		4,509		8,289		10,200		18,489		4,447	2006	(a)	40 years
2914 Third Avenue Bronx, NY		—			11,108		8,038		4,788		11,855		12,079		23,934		3,085	2006	(a)	40 years
West Shore Expressway Staten Island, NY		—			3,380		13,499		—		3,380		13,499		16,879		4,496	2007	(a)	40 years
West 54th Street Manhattan, NY		—			16,699		18,704		1,234		16,699		19,938		36,637		6,184	2007	(a)	40 years
5-7 East 17th Street Manhattan, NY		—			3,048		7,281		6,133		3,048		13,414		16,462		2,855	2008	(a)	40 years
651-671 W Diversey Chicago, IL		—			8,576		17,256		8		8,576		17,264		25,840		3,273	2011	(a)	40 years
15 Mercer Street New York, NY		—			1,887		2,483		—		1,887		2,483		4,370		466	2011	(a)	40 years
4401 White Plains Bronx, NY		—			1,581		5,054		—		1,581		5,054		6,635		927	2011	(a)	40 years
Chicago Street Retail Portfolio Chicago, IL		—			27,588		52,274		14,804		27,626		67,040		94,666		13,063	2012	(a)	40 years
1520 Milwaukee Avenue Chicago, IL		—			2,110		1,306		290		2,110		1,596		3,706		243	2012	(a)	40 years
330-340 River Street Cambridge, MA		11,396			8,404		14,235		—		8,404		14,235		22,639		2,547	2012	(a)	40 years
Rhode Island Place Shopping Center Washington, D.C.		—			7,458		15,968		1,924		7,458		17,892		25,350		3,314	2012	(a)	40 years
930 Rush Street Chicago, IL		—			4,933		14,587		—		4,933		14,587		19,520		2,461	2012	(a)	40 years
28 Jericho Turnpike Westbury, NY		13,918			6,220		24,416		—		6,220		24,416		30,636		4,215	2012	(a)	40 years
181 Main Street Westport, CT		—			1,908		12,158		407		1,908		12,565		14,473		1,943	2012	(a)	40 years
83 Spring Street Manhattan, NY		—			1,754		9,200		—		1,754		9,200		10,954		1,495	2012	(a)	40 years
60 Orange Street Bloomfield, NJ		7,266			3,609		10,790		—		3,609		10,790		14,399		1,859	2012	(a)	40 years
179-53 & 1801-03 Connecticut Avenue Washington, D.C.		—			11,690		10,135		1,014		11,690		11,149		22,839		1,863	2012	(a)	40 years
639 West Diversey Chicago, IL		—			4,429		6,102		916		4,429		7,018		11,447		1,283	2012	(a)	40 years
664 North Michigan Chicago, IL		—			15,240		65,331		—		15,240		65,331		80,571		9,601	2013	(a)	40 years
8-12 E. Walton Chicago, IL		—			5,398		15,601		977		5,398		16,578		21,976		2,394	2013	(a)	40 years
3200-3204 M Street Washington, DC		—			6,899		4,249		168		6,899		4,417		11,316		693	2013	(a)	40 years
868 Broadway Manhattan, NY		—			3,519		9,247		5		3,519		9,252		12,771		1,174	2013	(a)	40 years
313-315 Bowery Manhattan, NY		—			—		5,516		—		—		5,516		5,516		1,116	2013	(a)	40 years
120 West Broadway Manhattan, NY		—			—		32,819		1,116		—		33,935		33,935		2,798	2013	(a)	40 years
11 E. Walton Chicago, IL		—			16,744		28,346		192		16,744		28,538		45,282		3,648	2014	(a)	40 years
61 Main Street Westport, CT		—			4,578		2,645		706		4,578		3,351		7,929		371	2014	(a)	40 years
865 W. North Avenue Chicago, IL		—			1,893		11,594		23		1,893		11,617		13,510		1,396	2014	(a)	40 years
152-154 Spring St. Manhattan, NY		—			8,544		27,001		—		8,544		27,001		35,545		3,184	2014	(a)	40 years
2520 Flatbush Ave Brooklyn, NY		—			6,613		10,419		248		6,613		10,667		17,280		1,299	2014	(a)	40 years
252-256 Greenwich Avenue Greenwich, CT		—			10,175		12,641		544		10,175		13,185		23,360		1,647	2014	(a)	40 years
Bedford Green Bedford Hills, NY		—			12,425		32,730		4,102		13,763		35,494		49,257		4,245	2014	(a)	40 years
131-135 Prince Street Manhattan, NY		—			—		57,536		242		—		57,778		57,778		11,605	2014	(a)	40 years
Shops at Grand Ave Queens, NY		—			20,264		33,131		1,965		20,264		35,096		55,360		3,651	2014	(a)	40 years
201 Needham Street Newton, MA		—			4,550		4,459		105		4,550		4,564		9,114		536	2014	(a)	40 years
City Center San Francisco, CA		—			36,063		109,098		16,814		36,063		125,912		161,975		10,585	2015	(a)	40 years
163 Highland Avenue Needham, MA		8,852			12,679		11,213		—		12,679		11,213		23,892		1,198	2015	(a)	40 years
Roosevelt Galleria Chicago, IL		—			4,838		14,574		13		4,838		14,587		19,425		1,223	2015	(a)	40 years
Route 202 Shopping Center Wilmington, DE		—			—		6,346		501		—		6,847		6,847		673	2015	(a)	40 years
991 Madison Avenue New York, NY		—			—		76,965		1,506		—		78,471		78,471		4,413	2016	(a)	40 years
165 Newbury Street Boston, MA		—			1,918		3,980		—		1,918		3,980		5,898		265	2016	(a)	40 years
Concord & Milwaukee Chicago, IL		2,728			2,739		2,746		—		2,739		2,746		5,485		175	2016	(a)	40 years
State & Washington Chicago, IL		24,439			3,907		70,943		20		3,907		70,963		74,870		4,138	2016	(a)	40 years
151 N. State Street Chicago, IL		13,882			1,941		25,529		—		1,941		25,529		27,470		1,542	2016	(a)	40 years
North & Kingsbury Chicago, IL		12,555			18,731		16,292		52		18,731		16,344		35,075		989	2016	(a)	40 years
Sullivan Center Chicago, IL		50,000			13,443		137,327		419		13,443		137,746		151,189		8,052	2016	(a)	40 years
California & Armitage Chicago, IL		2,566			6,770		2,292		2		6,770		2,294		9,064		148	2016	(a)	40 years
555 9th Street San Francisco, CA		60,000			75,591		73,268		1		75,591		73,269		148,860		4,000	2016	(a)	40 years
Market Square Wilmington, DE		—			8,100		31,221		228		8,100		31,449		39,549		937	2017	(a)	40 years
Undeveloped Land		—			100		—		—		100		—		100		—
Fund II:
City Point Brooklyn, NY		224,587			—		100,316		468,337		—		568,653		568,653		29,640	2007	(c)	40 years
Fund III:
654 Broadway Manhattan, NY		—			9,040		3,654		3,497		9,040		7,151		16,191		1,209	2011	(a)	40 years
640 Broadway Manhattan, NY		49,470			12,503		19,960		14,304		12,503		34,264		46,767		5,798	2012	(a)	40 years
Cortlandt Crossing Mohegan Lake, NY		26,000			11,000		—		64,870		12,750		63,120		75,870		415	2012	(c)	40 years
3104 M Street Washington, DC		4,531			750		2,115		5,162		750		7,277		8,027		566	2013	(c)	40 years
3780-3858 Nostrand Avenue Brooklyn, NY		10,097			6,229		11,216		6,365		6,229		17,581		23,810		2,857	2013	(a)	40 years
Fund IV:
210 Bowery Manhattan, NY		—			1,875		5,625		6,021		1,875		11,646		13,521		26	2012	(c)	40 years
Paramus Plaza Paramus, NJ		17,627			11,052		7,037		11,934		11,052		18,971		30,023		2,836	2013	(a)	40 years
938 W. North Avenue Chicago, IL		14,100			2,314		17,067		5,362		2,314		22,429		24,743		2,473	2013	(a)	40 years
27 E. 61st Street Manhattan, NY		—			4,813		14,438		7,100		4,813		21,538		26,351		666	2014	(c)	40 years
17 E. 71st Street Manhattan, NY		18,906			7,391		20,176		280		7,391		20,456		27,847		2,211	2014	(a)	40 years
1035 Third Avenue Manhattan, NY		38,434			12,759		37,431		5,386		14,099		41,477		55,576		4,222	2015	(a)	40 years
801 Madison Avenue Manhattan, NY		—			4,178		28,470		5,608		4,178		34,078		38,256		1,054	2015	(c)	40 years
2208-2216 Fillmore Street San Francisco, CA		5,606			3,027		6,376		32		3,027		6,408		9,435		511	2015	(a)	40 years
146 Geary Street San Francisco, CA		27,700			9,500		28,500		489		9,500		28,989		38,489		2,257	2015	(a)	40 years
2207 Fillmore Street San Francisco, CA		1,120			1,498		1,735		118		1,498		1,853		3,351		143	2015	(a)	40 years
1964 Union Street San Francisco, CA		1,463			563		1,688		1,867		563		3,555		4,118		121	2016	(c)	40 years
Restaurants at Fort Point Boston, MA		6,201			1,041		10,905		—		1,041		10,905		11,946		818	2016	(a)	40 years
Wakeforest Crossing Wake Forest, NC		23,706			7,570		24,829		220		7,570		25,049		32,619		1,799	2016	(a)	40 years
Airport Mall Bangor, ME		5,476			2,294		7,067		458		2,294		7,525		9,819		526	2016	(a)	40 years
Colonie Plaza Albany, NY		11,890			2,852		9,619		271		2,852		9,890		12,742		632	2016	(a)	40 years
Dauphin Plaza Harrisburg, PA		10,021			5,290		9,464		2,235		5,290		11,699		16,989		793	2016	(a)	40 years
JFK Plaza Waterville, ME		4,381			751		5,991		9		751		6,000		6,751		412	2016	(a)	40 years
Mayfair Shopping Center Philadelphia, PA		—			6,178		9,266		741		6,178		10,007		16,185		602	2016	(a)	40 years
Shaw's Plaza Waterville, ME		7,840			828		11,814		56		828		11,870		12,698		721	2016	(a)	40 years
Wells Plaza Wells, ME		3,286			1,892		2,585		236		1,892		2,821		4,713		245	2016	(a)	40 years
717 N. Michigan Chicago, IL		18,972			20,674		10,093		1		20,674		10,094		30,768		523	2016	(c)	40 years
Shaw's Plaza North Windham, ME		5,848			1,876		6,696		1		1,876		6,697		8,573		281	2017	(a)	40 years
Lincoln Place Fairview Heights, IL		23,100			7,149		22,201		920		7,149		23,121		30,270		1,218	2017	(a)	40 years
Broughton Street Portfolio (BSP I) Savannah, GA		19,773			9,930		21,905		—		9,930		21,905		31,835		136	2018	(a)	40 years
Fund V:
Plaza Santa Fe Santa Fe, NM		22,893			—		28,214		69		—		28,283		28,283		1,228	2017	(a)	40 years
Hickory Ridge Hickory, NC		28,613			7,852		29,998		75		7,852		30,073		37,925		1,166	2017	(a)	40 years
New Towne Plaza Canton, MI		16,900			5,040		17,391		106		5,040		17,497		22,537		713	2017	(a)	40 years
Fairlane Green Allen Park, MI		40,300			18,121		37,143		247		18,121		37,390		55,511		1,026	2017	(a)	40 years
Trussville Promenade Birmingham, AL		29,370			7,587		34,285		—		7,587		34,285		41,872		778	2018	(a)	40 years
Elk Grove Commons Elk Grove, CA		—			6,204		48,008		28		6,204		48,036		54,240		525	2018	(a)	40 years
Hiram Pavilion I & II Hiram, GA		—			13,029		25,446		27		13,029		25,473		38,502		137	2018	(a)	40 years

Real Estate Under Development		47,645			65,297		31,473		23,527		65,297		55,000		120,297		—
Debt of Assets Held for Sale		—			—		—		—		—		—		—		—
Unamortized Loan Costs		(10,173	)		—		—		—		—		—		—		—
Unamortized Premium		753			—		—		—		—		—		—		—
Total	$	1,017,288		$	769,582	$	2,079,002	$	849,221	$	775,766	$	2,922,039	$	3,697,805	$	416,657

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, 2018.

The following table reconciles the activity for real estate properties from January 1, 2016 to December 31, 2018 (in thousands):

	Year Ended December 31,
	2018			2017			2016
Balance at beginning of year	$	3,466,482		$	3,382,000		$	2,736,283
Other improvements		100,077			55,763			152,129
Property acquisitions		134,559			179,292			761,400
Property dispositions or held for sale assets		(34,666	)		(189,895	)		(134,332	)
Other		(483	)		—			(9,844	)
Deconsolidation of previously consolidated investments		—			—			(123,636	)
Consolidation of previously unconsolidated investments		31,836			39,322			—
Balance at end of year	$	3,697,805		$	3,466,482		$	3,382,000

The following table reconciles accumulated depreciation from January 1, 2016 to December 31, 2018 (in thousands):

	Year Ended December 31,
	2018			2017			2016
Balance at beginning of year	$	339,862		$	287,066		$	298,703
Depreciation related to real estate		78,453			73,268			49,269
Property dispositions		(1,658	)		(20,472	)		(27,829	)
Deconsolidation of previously consolidated investments		—			—			(33,077	)
Balance at end of year	$	416,657		$	339,862		$	287,066

SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE

12 Months Ended

Dec. 31, 2018

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, 2018
First Mortgage Loan	6.0%	4/30/2020	$	15,000	$	17,802
First Mortgage Loan	8.1%	4/30/2019		153,400		38,673
Zero Coupon Loan	2.5%	5/31/2020		29,793		32,582
Mezzanine Loan	18.0%	7/1/2020		3,007		5,306
Preferred Equity	15.3%	2/3/2021		14,000		15,250
Total			$	215,200	$	109,613

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, 2016 to December 31, 2018 (in thousands):

	Reconciliation of Loans on Real Estate
	Year Ended December 31,
	2018			2017			2016
Balance at beginning of year	$	153,829		$	276,163		$	147,188
Additions		3,805			11,371			171,794
Repayments		(26,000	)		(32,000	)		(42,819	)
Conversion to real estate through receipt of deed		(22,021	)		(101,705	)		—
Balance at end of year	$	109,613		$	153,829		$	276,163

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

12 Months Ended

Dec. 31, 2018

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Segments

Principles of Consolidation

Use of Estimates

Reclassifications

Real Estate

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

Dispositions of Real Estate

Real Estate Held for Sale

Notes Receivable

Investments in and Advances to Unconsolidated Joint Ventures

Cash and Cash Equivalents

Restricted Cash

Deferred Costs

Derivative Instruments and Hedging Activities

NonControlling Interests

Noncontrolling Interests

Revenue Recognition and Accounts Receivable

Stock-Based Compensation

Income Taxes

Recently Issued Accounting Pronouncements

Recently Adopted Accounting Pronouncements

Recently adopted accounting pronouncements include those adopted during the year ended December 31, 2018.

Recently Issued Accounting Pronouncements

Lease Accounting

•

ASU 2016-02 also includes a practical expedient to use hindsight in determining the lease term or assessing purchase options for existing leases and in assessing impairment of right of use assets;

•

A new practical expedient under ASU 2018-11, described below.

In July 2018, the FASB issued ASU No. 2018-10, Codification Improvements to Topic 842, Leases. These amendments provide minor clarifications and corrections to ASU 2016-02, Leases (Topic 842).

Other Accounting Topics

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

12 Months Ended

Dec. 31, 2018

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Schedule of Operating Partnership's Equity Interest

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, 2018		Unfunded Commitment		Equity Interest Held By Operating Partnership^(a)			Preferred Return			Total Distributions as of December 31, 2018 ^(b)
Fund II and Mervyns II ^(c)	6/2004		28.33	%	$	347.1	$	—		28.33	%		8	%	$	146.6
Fund III	5/2007		24.54	%		423.9		26.1		24.54	%		6	%		551.9
Fund IV	5/2012		23.12	%		420.8		109.2		23.12	%		6	%		147.4
Fund V	8/2016		20.10	%		85.1		434.9		20.10	%		6	%		—

(a)	Amount represents the current economic ownership at December 31, 2018, 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.

(c)	During April 2018, a distribution of $15.0 million was made to the Fund II investors, including $4.3 million to the Operating Partnership. This amount remains subject to re-contribution to Fund II until April 2021.

Real Estate (Tables)

12 Months Ended

Dec. 31, 2018

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,
	2018			2017
Land	$	710,469		$	658,835
Buildings and improvements		2,594,828			2,406,488
Tenant improvements		151,154			131,850
Construction in progress		44,092			18,642
Properties under capital lease		76,965			76,965
Total		3,577,508			3,292,780
Less: Accumulated depreciation		(416,657	)		(339,862	)
Operating real estate, net		3,160,851			2,952,918
Real estate under development, at cost		120,297			173,702
Net investments in real estate	$	3,281,148		$	3,126,620

Schedule of Business Acquisitions, by Acquisition

During the years ended December 31, 2018 and December 31, 2017, the Company acquired the following consolidated retail properties (dollars in thousands):

Property and Location	Percent Acquired	Date of Acquisition	Purchase Price
2018 Acquisitions and Conversions
Core
Bedford Green Land Parcel - Bedford Hills, NY	100%	Mar 23, 2018	$	1,337
Subtotal Core				1,337

Fund IV
Broughton Street Partners I - Savannah, GA (Conversion) (Note 4)	100%	Oct 11, 2018		36,104
Subtotal Fund IV				36,104

Fund V
Trussville Promenade - Trussville, AL	100%	Feb 21, 2018		45,259
Elk Grove Commons - Elk Grove, CA	100%	Jul 18, 2018		59,320
Hiram Pavilion - Hiram, GA	100%	Oct 23, 2018		44,443
Subtotal Fund V				149,022
Total 2018 Acquisitions and Conversions			$	186,463

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

Schedule of Purchase Price Allocations

The following table summarizes the allocation of the purchase price of properties acquired during the years ended December 31, 2018 and December 31, 2017 (in thousands):

	Year Ended December 31,
	2018			2017
Net Assets Acquired
Land	$	38,086		$	48,138
Buildings and improvements		129,586			173,576
Other assets		—			84
Acquisition-related intangible assets (Note 6)		26,693			44,269
Acquisition-related intangible liabilities (Note 6)		(7,902	)		(11,535	)
Net assets acquired	$	186,463		$	254,532

Consideration
Cash	$	147,985		$	200,429
Conversion of note receivable	—				41,010
Liabilities assumed		2,597			3,363
Existing interest in previously unconsolidated investment		35,881			4,159
Change in control of previously unconsolidated investment	—				5,571
Total Consideration	$	186,463		$	254,532

Schedule of Property Dispositions

During the years ended December 31, 2018 and December 31, 2017, the Company disposed of the following consolidated properties (in thousands):

Property and Location	Owner	Date Sold	Sale Price		Gain (Loss) on Sale
2018 Disposition
Sherman Avenue - New York, NY	Fund II	Apr 17, 2018	$	26,000	$	33
Lake Montclair - Dumfries, VA	Fund IV	Aug 27, 2018		22,450		2,923
1861 Union Street - San Francisco, CA	Fund IV	Aug 29, 2018		6,000		2,184
210 Bowery - 4 Residential Condos - New York, NY	Fund IV	Nov 30, 2018, Dec 10, 2018, Dec 17, 2018, Dec 21, 2018		12,050		—
Total 2018 Dispositions			$	66,500	$	5,140

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

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

	Year Ended December 31,
	2018			2017			2016
Revenues	$	1,968		$	16,249		$	20,097
Expenses		(1,874	)		(20,529	)		(17,079	)
Loss (income) from continuing operations of disposed properties before gain on disposition of properties		94			(4,280	)		3,018
Gain on disposition of properties		5,140			48,886			81,965
Net income attributable to noncontrolling interests		(3,368	)		(32,254	)		(70,714	)
Net income attributable to Acadia	$	1,866		$	12,352		$	14,269

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, 2017				Year Ended 2018						December 31, 2018
	Number of Properties		Carrying Value		Transfers In		Capitalized Costs		Transfers Out		Number of Properties		Carrying Value
Core		2	$	21,897	$	—	$	6,320	$	20,458		1	$	7,759
Fund II		—		4,908		—		2,554		—		—		7,462
Fund III		2		63,939		—		36,117		78,814		1		21,242
Fund IV		1		82,958		—		876		—		1		83,834
Total		5	$	173,702	$	—	$	45,867	$	99,272		3	$	120,297

- 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3A
-URI http://asc.fasb.org/extlink&oid=109226691&loc=SL51724579-110230

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109222650&loc=d3e1474-107760

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5D
-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721677-107760

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=109222160&loc=SL51721533-107759

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 3A
-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721659-107760

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 4B
-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721665-107760

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
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-Paragraph 5C
-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721675-107760

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 205
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-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721683-107760

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
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-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=109222650&loc=d3e1361-107760

Reference 11: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5A
-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721671-107760

Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760

Reference 13: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 4A
-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721663-107760

+ Details

Notes Receivable, Net (Tables)

12 Months Ended

Dec. 31, 2018

Accounts And Notes Receivable Net [Abstract]

Schedule of Notes Receivable

	December 31,		December 31,		December 31, 2018
Description	2018		2017		Number		Maturity Date	Interest Rate
Core Portfolio	$	56,475	$	101,695		2	Apr 2019 - Apr 2020	6.0% - 8.1%
Fund II		32,582		31,778		1	May 2020	2.5%
Fund III		5,306		5,106		1	Jul 2020	18.0%
Fund IV		15,250		15,250		1	Feb 2021	15.3%
	$	109,613	$	153,829		5

Investments in and Advances to Unconsolidated Affiliates (Tables)

12 Months Ended

Dec. 31, 2018

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,			December 31,
Portfolio	Property	December 31, 2018	2018			2017
Core:
	840 N. Michigan^(a)	88.43%	$	65,013		$	69,846
	Renaissance Portfolio	20%		32,458			35,041
	Gotham Plaza	49%		29,550			29,416
	Town Center^{(a, b)}	75.22%		99,758			78,801
	Georgetown Portfolio	50%		4,653			3,479
				231,432			216,583

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

Fund III:
	Fund III Other Portfolio	90%		21			167
	Self Storage Management ^(d)	95%		206			206
				227			373
Fund IV:
	Broughton Street Portfolio ^(e)	50%		3,236			48,335
	Fund IV Other Portfolio	90%		14,540			20,199
	650 Bald Hill Road	90%		12,880			13,609
				30,656			82,143

Various Funds:	Due (to) from Related Parties ^(f)			(461	)		2,415
	Other ^(g)			556			556
	Investments in and advances to unconsolidated affiliates		$	262,410		$	302,070

Core:
	Crossroads ^(h)	49%	$	15,623		$	15,292
	Distributions in excess of income from, and investments in, unconsolidated affiliates		$	15,623		$	15,292

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

(b)	During November 2017 and March 2018, as discussed below, the Company increased its ownership in Town Center.

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

(d)	Represents a variable interest entity for which the Company was determined not to be the primary beneficiary.

(e)

(f)	Represents deferred fees.

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

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

Schedule of Condensed Balance Sheet

	December 31,
	2018			2017
Combined and Condensed Balance Sheets
Assets:
Rental property, net	$	488,000		$	518,900
Real estate under development		—			26,681
Investment in unconsolidated affiliates		6,853			6,853
Other assets		91,497			100,901
Total assets	$	586,350		$	653,335
Liabilities and partners’ equity:
Mortgage notes payable	$	408,967		$	405,652
Other liabilities		54,675			61,932
Partners’ equity		122,708			185,751
Total liabilities and partners’ equity	$	586,350		$	653,335

Company's share of accumulated equity	$	141,384		$	185,533
Basis differential		104,084			95,358
Deferred fees, net of portion related to the Company's interest		1,780			3,472
Amounts (payable) receivable by the Company		(461	)		2,415
Investments in and advances to unconsolidated affiliates, net of Company's share of distributions in excess of income from and investments in unconsolidated affiliates		246,787			286,778
Company's share of distributions in excess of income from and investments in unconsolidated affiliates		15,623			15,292
Investments in and advances to unconsolidated affiliates	$	262,410		$	302,070

Schedule of Condensed Income Statement

	Year Ended December 31,
	2018			2017			2016
Combined and Condensed Statements of Income
Total revenues	$	80,184		$	83,222		$	84,218
Operating and other expenses		(23,586	)		(24,711	)		(25,724	)
Interest expense		(19,954	)		(18,733	)		(16,300	)
Depreciation and amortization		(22,228	)		(24,192	)		(35,432	)
Loss on debt extinguishment		—			(154	)		—
(Loss) gain on disposition of properties		(1,673	)		18,957			(1,340	)
Net income attributable to unconsolidated affiliates	$	12,743		$	34,389		$	5,422

Company’s share of equity in net income of unconsolidated affiliates	$	12,345		$	26,039		$	40,538
Basis differential amortization		(3,043	)		(2,668	)		(1,089	)
Company’s equity in earnings of unconsolidated affiliates	$	9,302		$	23,371		$	39,449

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

12 Months Ended

Dec. 31, 2018

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)	2018			2017
Other Assets, Net:
Lease intangibles, net (Note 6)	$	115,939		$	127,571
Deferred charges, net ^(a)		28,619			24,589
Prepaid expenses		18,422			16,838
Other receivables		5,058			11,356
Accrued interest receivable		17,046			11,668
Deposits		4,611			6,296
Due from seller		4,000			4,300
Deferred tax assets		2,032			2,096
Derivative financial instruments (Note 8)		7,018			4,402
Due from related parties		1,802			1,479
Corporate assets		1,953			2,369
Income taxes receivable		2,070			1,995
	$	208,570		$	214,959

(a) Deferred Charges, Net:
Deferred leasing and other costs	$	45,011		$	41,020
Deferred financing costs related to line of credit		8,960			7,786
		53,971			48,806
Accumulated amortization		(25,352	)		(24,217	)
Deferred charges, net	$	28,619		$	24,589

Accounts Payable and Other Liabilities:
Lease intangibles, net (Note 6)	$	95,045		$	104,478
Accounts payable and accrued expenses		65,215			61,420
Deferred income		34,052			31,306
Tenant security deposits, escrow and other		10,588			10,029
Derivative financial instruments (Note 8)		7,304			1,467
Income taxes payable		19			176
Other		2,738			1,176
	$	214,961		$	210,052

Lease Intangibles (Tables)

12 Months Ended

Dec. 31, 2018

Goodwill And Intangible Assets Disclosure [Abstract]

Schedule of Intangible Assets and Liabilities Included in Other Assets and Other Liabilities

Intangible assets and liabilities are included in other assets and other liabilities (Note 5) on the consolidated balance sheet and summarized as follows (in thousands):

	December 31, 2018									December 31, 2017
	Gross Carrying Amount			Accumulated Amortization			Net Carrying Amount			Gross Carrying Amount			Accumulated Amortization			Net Carrying Amount
Amortizable Intangible Assets
In-place lease intangible assets	$	216,021		$	(105,972	)	$	110,049		$	193,821		$	(72,749	)	$	121,072
Above-market rent		18,169			(12,279	)		5,890			16,786			(10,287	)		6,499
	$	234,190		$	(118,251	)	$	115,939		$	210,607		$	(83,036	)	$	127,571

Amortizable Intangible Liabilities
Below-market rent	$	(152,188	)	$	57,721		$	(94,467	)	$	(147,232	)	$	43,391		$	(103,841	)
Above-market ground lease		(671	)		93			(578	)		(671	)		34			(637	)
	$	(152,859	)	$	57,814		$	(95,045	)	$	(147,903	)	$	43,425		$	(104,478	)

Scheduled Amortization of Acquired Lease Intangible Assets and Assumed Liabilities

The scheduled amortization of acquired lease intangible assets and assumed liabilities as of December 31, 2018 is as follows (in thousands):

Years Ending December 31,	Net Increase in Lease Revenues		Increase to Amortization			Reduction of Rent Expense		Net Income (Expense)
2019	$	8,431	$	(27,309	)	$	58	$	(18,820	)
2020		8,206		(20,511	)		58		(12,247	)
2021		7,725		(15,196	)		58		(7,413	)
2022		7,346		(10,467	)		58		(3,063	)
2023		7,053		(8,192	)		58		(1,081	)
Thereafter		49,816		(28,374	)		288		21,730
Total	$	88,577	$	(110,049	)	$	578	$	(20,894	)

Debt (Tables)

12 Months Ended

Dec. 31, 2018

Debt Disclosure [Abstract]

Summary of Consolidated Indebtedness

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

	Interest Rate at				Carrying Value at
	December 31,	December 31,		Maturity Date at	December 31,			December 31,
	2018	2017		December 31, 2018	2018			2017
Mortgages Payable
Core Fixed Rate	3.88%-6.00%	3.88%-5.89%		Feb 2024 - Apr 2035	$	178,271		$	179,870
Core Variable Rate - Swapped ⁽^a)	3.41%-5.67%	3.41%-5.67%		Jan 2023 - Nov 2028		82,583			74,152
Total Core Mortgages Payable						260,854			254,022
Fund II Fixed Rate	1.00%-4.75%	1.00%-4.75%		May 2020 - Aug 2042		205,262			205,262
Fund II Variable Rate - Swapped ⁽^a)	4.27%	4.27%		Nov 2021		19,325			19,560
Total Fund II Mortgages Payable						224,587			224,822
Fund III Variable Rate	LIBOR+2.65%-LIBOR+4.65%	Prime+0.50%-LIBOR+4.65%		Jun 2020 - Dec 2021		90,096			65,866
Fund IV Fixed Rate	3.40%-4.50%	3.40%-4.50%		Oct 2025 - Jun 2026		8,189			10,503
Fund IV Variable Rate	LIBOR+1.60%-LIBOR+3.95%	LIBOR+1.70%-LIBOR+3.95%		Feb 2019 - Aug 2021		233,065			250,584
Fund IV Variable Rate - Swapped ⁽^a)	3.67%-4.23%	3.67%-4.23%		May 2019 - Dec 2022		71,841			86,851
Total Fund IV Mortgages Payable						313,095			347,938
Fund V Variable Rate	LIBOR+2.15%-LIBOR+2.25%	LIBOR+2.25%		Oct 2020 - Jan 2021		51,506			28,613
Fund V Variable Rate - Swapped ^(a)	4.61%-4.78%		—	Feb 2021 - Jun 2021		86,570			—
Total Fund V Mortgage Payable						138,076			28,613
Net unamortized debt issuance costs						(10,173	)		(12,943	)
Unamortized premium						753			856
Total Mortgages Payable					$	1,017,288		$	909,174
Unsecured Notes Payable
Core Term Loans	LIBOR+1.25%		—	Mar 2023	$	383		$	—
Core Variable Rate Unsecured Term Loans - Swapped ^(a)	2.49%-4.05%	2.54%-3.59%		Mar 2023		349,617			300,000
Total Core Unsecured Notes Payable						350,000			300,000
Fund II Unsecured Notes Payable	LIBOR+1.65%	LIBOR+1.40%		Sep 2020		40,000			31,500
Fund IV Term Loan/Subscription Facility	LIBOR+1.65%-LIBOR+2.75%	LIBOR+1.65%-LIBOR+2.75%		Oct 2019 - Dec 2019		40,825			40,825
Fund V Subscription Facility	LIBOR+1.60%	LIBOR+1.60%		May 2020		102,800			103,300

Net unamortized debt issuance costs						(368	)		(1,890	)
Total Unsecured Notes Payable					$	533,257		$	473,735
Unsecured Line of Credit
Core Unsecured Line of Credit	LIBOR+1.35%	LIBOR+1.40%		Mar 2022	$	—		$	18,048
Core Unsecured Line of Credit - Swapped ^(a)	4.15%-5.02%	4.20%-5.07%		Mar 2022		—			23,452
Total Unsecured Line of Credit					$	—		$	41,500

Total Debt - Fixed Rate ^(b)					$	1,001,658		$	899,650
Total Debt - Variable Rate ^(c)						558,675			538,736
Total Debt						1,560,333			1,438,386
Net unamortized debt issuance costs						(10,541	)		(14,833	)
Unamortized premium						753			856
Total Indebtedness					$	1,550,545		$	1,424,409

(a)

(b)	Includes $609.9 million and $504.0 million, respectively, of variable-rate debt that has been fixed with interest rate swap agreements as of the periods presented.

(c)	Includes $143.8 million and $141.1 million, respectively, of variable-rate debt that is subject to interest cap agreements.

Scheduled Principal Repayments

The scheduled principal repayments of the Company’s consolidated indebtedness, as of December 31, 2018 are as follows (in thousands):

Year Ending December 31,
2019	$	219,118
2020		527,304
2021		180,511
2022		48,528
2023		370,680
Thereafter		214,192
		1,560,333
Unamortized premium		753
Net unamortized debt issuance costs		(10,541	)
Total indebtedness	$	1,550,545

Financial Instruments and Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2018

Fair Value Disclosures [Abstract]

Schedule of Assets and Liabilities Measured at Fair Value 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, 2018						December 31, 2017
	Level 1		Level 2		Level 3		Level 1		Level 2		Level 3
Assets
Money Market Funds	$	4,504	$	—	$	—	$	3	$	—	$	—
Derivative financial instruments		—		7,018		—		—		4,402		—
Liabilities
Derivative financial instruments		—		7,304		—		—		1,467		—

Schedule of Derivative Financial Instruments

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

					Strike Rate								Fair Value
Derivative Instrument	Aggregate Notional Amount		Effective Date	Maturity Date	Low				High			Balance Sheet Location	December 31, 2018			December 31, 2017
Core
Interest Rate Swaps	$	111,117	Dec 2012 - Jul 2020	Dec 2022 - Jul 2030		2.80	%	—		3.77	%	Other Liabilities ^(a)	$	(6,332	)	$	(1,438	)
Interest Rate Swaps		321,083	Feb 2013 - Dec 2017	Nov 2019 - Jul 2027		1.24	%	—		3.77	%	Other Assets		6,022			4,076
	$	432,200											$	(310	)	$	2,638

Fund II
Interest Rate Swap	$	19,325	Oct 2014	Nov 2021		2.88	%	—		2.88	%	Other Assets	$	108		$	—
Interest Rate Swap		—	Oct 2014	Nov 2021		2.88	%	—		2.88	%	Other Liabilities		—			(29	)
	$	19,325											$	108		$	(29	)

Fund III
Interest Rate Cap	$	58,000	Dec 2016	Jan 2020		3.00	%	—		3.00	%	Other Assets	$	8		$	14

Fund IV
Interest Rate Swaps	$	71,841	Mar 2017 - Nov 2017	Mar 2020 - Dec 2022		1.82	%	—		2.11	%	Other Assets	$	851		$	295
Interest Rate Caps		108,900	July 2016 - Nov 2016	Aug 2019 - Dec 2019		3.00	%	—		3.00	%	Other Assets		8			17
	$	180,741											$	859		$	312

Fund V
Interest Rate Swap	$	16,900	Jan 2018	Feb 2021		2.41	%	—		2.41	%	Other Assets	$	21		$	—
Interest Rate Swaps		69,670	Jun 2018	Jun 2021 - Jun 2023		2.78	%	—		2.88	%	Other Liabilities		(972	)		—
	$	86,570											$	(951	)	$	—

Total asset derivatives													$	7,018		$	4,402
Total liability derivatives													$	(7,304	)	$	(1,467	)

(a)

Includes two swaps with a fair value of ($2.9) million which were acquired during July 2018 and are not effective until July 2020.

Financial statements of Income (Losses) Recognized Related to Cash Flow Hedges

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,
	2018			2017		2016
Amount of (loss) income recognized in other comprehensive income	$	(2,659	)	$	634	$	(646	)
Amount of loss subsequently reclassified to earnings		71			3,317		4,576

Schedule of Other Financial Instruments Carrying Values and Fair values

			December 31, 2018				December 31, 2017
	Level		Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
Notes Receivable ^(a)		3	$	109,613	$	107,370	$	153,829	$	151,712
Mortgage and Other Notes Payable ^(a)		3		1,026,708		1,021,075		921,261		921,891
Investment in non-traded equity securities ^(b)		3		—		23,208		—		22,824
Unsecured notes payable and Unsecured line of credit ^(c)		2		533,625		533,954		517,125		515,330

(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, 2018

Stockholders Equity Including Portion Attributable To Noncontrolling Interest [Abstract]

Summary of Activity in Accumulated Other Comprehensive Income

The following table sets forth the activity in accumulated other comprehensive income for the years ended December 31, 2018, 2017 and 2016 (in thousands):

	Gains or Losses on Derivative Instruments
Balance at January 1, 2018	$	2,614

Other comprehensive loss before reclassifications		(2,659	)
Reclassification of realized interest on swap agreements		71
Net current period other comprehensive loss		(2,588	)
Net current period other comprehensive loss attributable to noncontrolling interests		490
Balance at December 31, 2018	$	516

Balance at January 1, 2017	$	(798	)

Other comprehensive income before reclassifications		634
Reclassification of realized interest on swap agreements		3,317
Net current period other comprehensive income		3,951
Net current period other comprehensive income 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 income		3,930
Net current period other comprehensive income attributable to noncontrolling interests		(265	)
Balance at December 31, 2016	$	(798	)

Summary of Change in Noncontrolling Interest

The following table summarizes the change in the noncontrolling interests for the years ended December 31, 2018, 2017 and 2016 (dollars in thousands):

	Noncontrolling Interests in Operating Partnership ^(a)			Noncontrolling Interests in Partially-Owned Affiliates ^(b)			Total
Balance at January 1, 2018	$	102,921		$	545,519		$	648,440
Distributions declared of $1.09 per Common OP Unit		(6,888	)		—			(6,888	)
Net income (loss) for the year ended December 31, 2018		2,572			(49,709	)		(47,137	)
Conversion of 117,978 Common OP Units to Common Shares by limited partners of the Operating Partnership		(2,068	)		—			(2,068	)
Other comprehensive loss - unrealized loss on valuation of swap agreements		(129	)		(681	)		(810	)
Reclassification of realized interest expense on swap agreements		(3	)		323			320
Noncontrolling interest contributions		—			47,560			47,560
Noncontrolling interest distributions		—			(24,793	)		(24,793	)
Employee Long-term Incentive Plan Unit Awards		12,374			—			12,374
Rebalancing adjustment ^(c)		(4,556	)		—			(4,556	)
Balance at December 31, 2018	$	104,223		$	518,219		$	622,442

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 year ended December 31, 2017		4,159			(1,321	)		2,838
Conversion of 81,453 Common OP Units and 5,000 Preferred OP Units to Common Shares by limited partners of the Operating Partnership		(1,541	)		—			(1,541	)
Other comprehensive income (loss) - unrealized gain (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 ^(c)		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 year ended 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		—			(25,925	)		(25,925	)
Other comprehensive loss - 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 ^(c)		(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)	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, 2018

Leases [Abstract]

Schedule of Future Minimum Rental Revenues and Payments for Operating and Capital Leases

Year Ending December 31,	Minimum Rental Revenues		Minimum Rental Payments
2019	$	187,158	$	4,775
2020		178,691		4,571
2021		159,749		4,354
2022		139,294		4,404
2023		121,456		4,425
Thereafter		513,853		180,618
Total	$	1,300,201	$	203,147

Segment Reporting (Tables)

12 Months Ended

Dec. 31, 2018

Segment Reporting [Abstract]

Summary of Segment Information

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

	As of or for the Year Ended December 31, 2018
	Core Portfolio			Funds			Structured Financing		Unallocated			Total
Revenues	$	167,894		$	94,319		$	—	$	—		$	262,213
Depreciation and amortization		(60,903	)		(56,646	)		—		—			(117,549	)
Property operating expenses, other operating and real estate taxes		(45,138	)		(37,642	)		—		—			(82,780	)
General and administrative expenses		—			—			—		(34,343	)		(34,343	)
Operating income		61,853			31			—		(34,343	)		27,541
Gain on disposition of properties		—			5,140			—		—			5,140
Interest income		—			—			13,231		—			13,231
Equity in earnings of unconsolidated affiliates inclusive of gains on disposition of properties ^(a)		7,415			1,887			—		—			9,302
Interest expense		(27,575	)		(42,403	)		—		—			(69,978	)
Income tax provision		—			—			—		(934	)		(934	)
Net income		41,693			(35,345	)		13,231		(35,277	)		(15,698	)
Net loss attributable to noncontrolling interests		752			46,385			—		—			47,137
Net income attributable to Acadia	$	42,445		$	11,040		$	13,231	$	(35,277	)	$	31,439

Real estate at cost	$	2,069,439		$	1,628,366		$	—	$	—		$	3,697,805
Total assets	$	2,232,695		$	1,616,472		$	109,613	$	—		$	3,958,780
Cash paid for acquisition of real estate	$	1,343		$	146,642		$	—	$	—		$	147,985
Cash paid for development and property improvement costs	$	32,662		$	62,172		$	—	$	—		$	94,834

	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	)
General and administrative expenses		—			—			—		(33,756	)		(33,756	)
Impairment charge		—			(14,455	)		—		—			(14,455	)
Operating income (loss)		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 ^(a)		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	$	42,026		$	66,116		$	—	$	—		$	108,142

	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 ^(a)		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

(a)

Share Incentive and Other Compensation (Tables)

12 Months Ended

Dec. 31, 2018

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Schedule of Unvested Restricted Shares and LTIP Units

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
Granted		22,817			23.65		425,880			26.80
Vested		(25,261	)		30.79		(431,827	)		29.72
Forfeited		(428	)		27.25		(12,266	)		28.57
Unvested at December 31, 2018		38,455		$	22.44		891,886		$	26.87

Federal Income Taxes (Tables)

12 Months Ended

Dec. 31, 2018

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)	2018			2017			2016
Net income attributable to Acadia	$	31,439		$	61,470		$	72,776
Deferred cancellation of indebtedness income		2,050			2,050			2,050
Deferred rental and other income ^(a)		1,222			(934	)		1,610
Book/tax difference - depreciation and amortization ^(a)		23,166			21,334			15,189
Straight-line rent and above- and below-market rent adjustments ^(a)		(12,129	)		(10,559	)		(7,882	)
Book/tax differences - equity-based compensation		6,042			5,325			10,307
Joint venture equity in earnings, net ^(a)		13,905			9,114			(2,011	)
Impairment charges and reserves		—			—			769
Acquisition costs ^(a)		326			1,135			5,116
Gains		—			(5,181	)		—
Book/tax differences - miscellaneous		(2,821	)		930			(4,924	)
Taxable income	$	63,200		$	84,684		$	93,000
Distributions declared	$	89,122		$	87,848		$	91,053

(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,
	2018					2017					2016
	Per Share		%			Per Share		%			Per Share		%
Ordinary income - Non-Section 199A		—		—	%	$	0.82		78	%	$	0.77		66	%
Ordinary income - Section 199A	$	0.87		100	%		—		—	%		—		—	%
Qualified dividend		—		—	%		—		—	%		—		—	%
Capital gain		—		—	%		0.23		22	%		0.39		34	%
Total ^(b)	$	0.87		100	%	$	1.05		100	%	$	1.16		100	%

(b)	The fourth quarter 2018 regular dividend was $0.28 per common share of which approximately $0.06 was allocable to 2018 and approximately $0.22 is allocable to 2019.

Schedule of TRS Income and Provision for Income Taxes

	Year Ended December 31,
	2018			2017			2016
TRS loss before income taxes	$	(2,609	)	$	(3,604	)	$	(1,583	)
(Provision) benefit for income taxes:
Federal		(377	)		(982	)		378
State and local		26			423			97
TRS net loss before noncontrolling interests		(2,960	)		(4,163	)		(1,108	)
Noncontrolling interests		4			8			(9	)
TRS net loss	$	(2,956	)	$	(4,155	)	$	(1,117	)

Schedule of Effective Income Tax Rate Reconciliation

	Year Ended December 31,
	2018			2017			2016
Federal tax benefit at statutory tax rate	$	(548	)	$	(1,225	)	$	(538	)
TRS state and local taxes, net of Federal benefit		(165	)		(190	)		(84	)
Tax effect of:
Permanent differences, net		951			1,131			1,663
Prior year over-accrual, net		—			(1,541	)		—
Effect of Tax Cuts and Jobs Act		—			1,982			—
Other		172			404			(1,516	)
REIT state and local income and franchise taxes		524			443			370
Total provision (benefit) for income taxes	$	934		$	1,004		$	(105	)

Earnings Per Common Share (Tables)

12 Months Ended

Dec. 31, 2018

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted

	Year Ended December 31,
(dollars in thousands)	2018			2017			2016
Numerator:
Net income attributable to Acadia	$	31,439		$	61,470		$	72,776
Less: net income attributable to participating securities		(267	)		(642	)		(793	)
Income from continuing operations net of income attributable to participating securities	$	31,172		$	60,828		$	71,983

Denominator:
Weighted average shares for basic earnings per share		82,080,159			83,682,789			76,231,000
Effect of dilutive securities:
Employee unvested restricted shares		—			2,682			12,550
Denominator for diluted earnings per share		82,080,159			83,685,471			76,243,550

Basic and diluted earnings per Common Share from continuing operations attributable to Acadia	$	0.38		$	0.73		$	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			136,593			141,593
Series C Preferred OP Units - Common share equivalent		474,278			479,978			410,207
Restricted shares		36,879			41,299			50,156

Summary of Quarterly Financial Information (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2018

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Financial Information

The quarterly results of operations of the Company for the years ended December 31, 2018 and 2017 are as follows (in thousands, except per share amounts):

	Three Months Ended ^(a)
	March 31, 2018			June 30, 2018			September 30, 2018			December 31, 2018
Revenues	$	63,124		$	63,569		$	66,075		$	69,445
Net loss		(4,160	)		(2,270	)		(2,597	)		(6,671	)
Net loss attributable to noncontrolling interests		11,579			9,935			11,822			13,801
Net income attributable to Acadia		7,419			7,665			9,225			7,130

Earnings per share attributable to Acadia:
Basic	$	0.09		$	0.09		$	0.11		$	0.09
Diluted		0.09			0.09			0.11			0.09

Weighted average number of shares:
Basic		83,434			81,756			81,566			81,591
Diluted		83,438			81,756			81,566			81,591

Cash dividends declared per Common Share	$	0.27		$	0.27		$	0.27		$	0.28

(a)	The three months ended September 30, 2018 includes an aggregate $5.1 million gain on the sales of two consolidated Fund IV properties (), of which $3.9 million was attributable to noncontrolling interests.

	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
Diluted	$	0.18		$	0.14	$	0.15		$	0.25
		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 ().

(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)

(d)

Organization, Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Details)	12 Months Ended
	Dec. 31, 2018 USD ($) property segment	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Limited partnership to common stock conversion ratio	100.00%
Number of retail properties \| property	171
Number of reportable segments \| segment	3
Amount of goodwill recorded and acquisition costs capitalized	$ 0
Deferred Rent Receivables, Net	47,200,000	$ 37,400,000
Allowance for doubtful accounts receivable	7,900,000	5,900,000
Net cash provided by (used in) investing activities	(136,619,000)	4,063,000	$ (613,564,000)
Net cash provided by (used in) operating activities	96,076,000	114,655,000	109,848,000
Net cash (used in) provided by financing activities	(10,278,000)	(127,758,000)	488,365,000
Capitalized acquisition costs	300,000
Acquisition costs expensed	2,100,000	2,100,000	8,200,000
Capitalized internal leasing costs	1,400,000	1,300,000
Accounting Standards Update 2014-09
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Cumulative effect of new accounting principle during period		0
Accounting Standards Update 2016-15
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Net cash provided by (used in) investing activities		6,300,000
Net cash provided by (used in) operating activities		6,300,000
Accounting Standards Update 2016-18
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Net cash provided by (used in) operating activities		11,500,000	1,900,000
Net cash (used in) provided by financing activities		900,000	$ 9,900,000
Accounting Standards Update 2016-02
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Leases, future payment obligations	$ 203,100,000
REIT
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Percentage of distribute taxable income	90.00%
Percentage of taxable income.	100.00%
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
Core Portfolio
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of retail properties \| property	118
Properties owned percentage	100.00%
Acquisition costs expensed		$ 1,200,000
Opportunity Funds
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of retail properties \| property	53
Operating Partnership, as General Partner or Managing Member
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Equity interest held by Operating Partnership	94.00%	94.00%
Remaining funds rate of distribution to operating partnership (in percent)	20.00%
Institutional Investors
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Remaining funds rate of distribution to all partners (in percent)	80.00%

Organization, Basis of Presentation and Summary of Significant Accounting Policies - Schedule of Operating Partnership's Equity Interest (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Apr. 30, 2018	Dec. 31, 2018
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		$ 146.6
Fund III
Variable Interest Entity [Line Items]
Operating Partnership Share of Capital		24.54%
Capital Called		$ 423.9
Unfunded Commitment		$ 26.1
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		$ 420.8
Unfunded Commitment		$ 109.2
Equity interest held by Operating Partnership		23.12%
Preferred Return		6.00%
Total Distributions		$ 147.4
Fund V
Variable Interest Entity [Line Items]
Operating Partnership Share of Capital		20.10%
Capital Called		$ 85.1
Unfunded Commitment		$ 434.9
Equity interest held by Operating Partnership		20.10%
Preferred Return		6.00%
Total Distributions		$ 0.0
Fund II
Variable Interest Entity [Line Items]
Total Distributions	$ 15.0
Operating Partnership, as General Partner or Managing Member
Variable Interest Entity [Line Items]
Total Distributions	$ 4.3

Real Estate - Schedule of Real Estate (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Acquisition And Disposition Of Properties And Discontinued Operations [Abstract]
Land	$ 710,469	$ 658,835
Buildings and improvements	2,594,828	2,406,488
Tenant improvements	151,154	131,850
Construction in progress	44,092	18,642
Properties under capital lease	76,965	76,965
Total	3,577,508	3,292,780
Less: Accumulated depreciation	(416,657)	(339,862)
Operating real estate, net	3,160,851	2,952,918
Real estate under development, at cost	120,297	173,702
Net investments in real estate	$ 3,281,148	$ 3,126,620

Real Estate - Schedule of Acquisitions and Conversions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Purchase Price	$ 186,463	$ 254,532
Core Portfolio
Business Acquisition [Line Items]
Purchase Price	$ 1,337	$ 42,800
Core Portfolio \| Bedford Green Land Parcel \| Bedford Hills, NY
Business Acquisition [Line Items]
Percent Acquired	100.00%
Purchase Price	$ 1,337
Core Portfolio \| Market Square Shopping Center \| Wilmington, DE
Business Acquisition [Line Items]
Percent Acquired		100.00%
Purchase Price		$ 42,800
Fund IV
Business Acquisition [Line Items]
Purchase Price	$ 36,104	$ 44,492
Fund IV \| Broughton Street Partners I \| Savannah, GA (Conversion)
Business Acquisition [Line Items]
Percent Acquired	100.00%
Purchase Price	$ 36,104
Fund IV \| Lincoln Place - Fairview Heights, IL \| Fairview Heights, IL
Business Acquisition [Line Items]
Percent Acquired		100.00%
Purchase Price		$ 35,350
Fund IV \| Shaw's Plaza Waterville, ME \| Windham, ME
Business Acquisition [Line Items]
Percent Acquired		100.00%
Purchase Price		$ 9,142
Fund V
Business Acquisition [Line Items]
Purchase Price	$ 149,022	$ 167,240
Fund V \| Trussville Promenade - Trussville, AL \| Trussville, AL
Business Acquisition [Line Items]
Percent Acquired	100.00%
Purchase Price	$ 45,259
Fund V \| Elk Grove Commons - Elk Grove, CA \| Elk Grove, CA
Business Acquisition [Line Items]
Percent Acquired	100.00%
Purchase Price	$ 59,320
Fund V \| Hiram Pavilion \| Hiram, GA
Business Acquisition [Line Items]
Percent Acquired	100.00%
Purchase Price	$ 44,443
Fund V \| Plaza Santa Fe - Santa Fe, NM \| Santa Fe, NM
Business Acquisition [Line Items]
Percent Acquired		100.00%
Purchase Price		$ 35,220
Fund V \| Hickory Ridge - Hickory, NC \| Hickory, NC
Business Acquisition [Line Items]
Percent Acquired		100.00%
Purchase Price		$ 44,020
Fund V \| New Towne Plaza - Canton, MI \| Canton, MI
Business Acquisition [Line Items]
Percent Acquired		100.00%
Purchase Price		$ 26,000
Fund V \| Fairlane Green \| Allen Park, MI
Business Acquisition [Line Items]
Percent Acquired		100.00%
Purchase Price		$ 62,000

Real Estate - Acquisitions and Conversions - Additional Information (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Capitalized acquisition costs									$ 300,000
Acquisition costs expensed									2,100,000	$ 2,100,000	$ 8,200,000
Debt assumed									0	0
Net (loss) income	$ (6,671,000)	$ (2,597,000)	$ (2,270,000)	$ (4,160,000)	$ 24,944,000	$ 13,285,000	$ 6,108,000	$ 19,971,000	(15,698,000)	64,308,000	$ 134,592,000
Consolidated Acquisitions And Conversions
Business Acquisition [Line Items]
Revenues									$ 9,000,000	$ 10,200,000
Type of Revenue [Extensible List]									us-gaap:RealEstateMember	us-gaap:RealEstateMember
Net (loss) income									$ 500,000	$ 3,500,000
Core Portfolio
Business Acquisition [Line Items]
Acquisition costs expensed										1,200,000
Fund Portfolio
Business Acquisition [Line Items]
Acquisition costs expensed										$ 900,000

Real Estate - Schedule of Purchase Price Allocations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Purchase Price Allocation
Land	$ 38,086	$ 48,138
Buildings and improvements	129,586	173,576
Other assets	0	84
Acquisition-related intangible assets (Note 6)	26,693	44,269
Acquisition-related intangible liabilities (Note 6)	(7,902)	(11,535)
Net assets acquired	186,463	254,532
Consideration
Cash	147,985	200,429
Conversion of note receivable	0	41,010
Liabilities assumed	2,597	3,363
Existing interest in previously unconsolidated investment	35,881	4,159
Change in control of previously unconsolidated investment	0	5,571
Total Consideration	$ 186,463	$ 254,532

Real Estate - Schedule of Property Dispositions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Sale	$ 5,140	$ 48,886	$ 81,965
Disposal Group, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Price	66,500	281,338
Gain (Loss) on Sale	$ 5,140	$ 48,886	$ 81,965
Fund II
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Date Sold	Apr. 17, 2018
Fund II \| Disposal Group, Not Discontinued Operations \| Sherman Avenue
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Date Sold	Apr. 17, 2018
Sale Price	$ 26,000
Gain (Loss) on Sale	$ 33
Fund II \| Disposal Group, Not Discontinued Operations \| 216th Street
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Date Sold		Sep. 11, 2017
Sale Price		$ 30,579
Gain (Loss) on Sale		$ 6,543
Fund II \| Disposal Group, Not Discontinued Operations \| City Point Condominium Tower I
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Date Sold		Oct. 13, 2017
Sale Price		$ 96,000
Gain (Loss) on Sale		$ (810)
Fund II \| Disposal Group, Not Discontinued Operations \| 260 E 161th Street
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Date Sold		Dec. 13, 2017
Sale Price		$ 105,684
Gain (Loss) on Sale		$ 31,537
Fund IV \| Disposal Group, Not Discontinued Operations \| Lake Montclair
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Date Sold	Aug. 27, 2018
Sale Price	$ 22,450
Gain (Loss) on Sale	$ 2,923
Fund IV \| Disposal Group, Not Discontinued Operations \| 1861 Union Street
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Date Sold	Aug. 29, 2018
Sale Price	$ 6,000
Gain (Loss) on Sale	$ 2,184
Fund IV \| Disposal Group, Not Discontinued Operations \| Bowery4 Residential Condos New York N Y \| Scenario One
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Date Sold	Nov. 30, 2018
Fund IV \| Disposal Group, Not Discontinued Operations \| Bowery4 Residential Condos New York N Y \| Scenario Two
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Date Sold	Dec. 10, 2018
Fund IV \| Disposal Group, Not Discontinued Operations \| Bowery4 Residential Condos New York N Y \| Scenario Three
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Date Sold	Dec. 17, 2018
Fund IV \| Disposal Group, Not Discontinued Operations \| Bowery4 Residential Condos New York N Y \| Scenario Four
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Date Sold	Dec. 21, 2018
Sale Price	$ 12,050
Fund IV \| Disposal Group, Not Discontinued Operations \| 1151 Third Avenue
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Date Sold		Nov. 16, 2017
Sale Price		$ 27,000
Gain (Loss) on Sale		$ 5,183
Fund III \| Disposal Group, Not Discontinued Operations \| New Hyde Park Shopping Center
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Date Sold		Jul. 06, 2017
Sale Price		$ 22,075
Gain (Loss) on Sale		$ 6,433

Real Estate - Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
STATEMENTS OF INCOME
Gain on disposition of properties	$ 5,140	$ 48,886	$ 81,965
Disposal Group, Not Discontinued Operations
STATEMENTS OF INCOME
Revenues	1,968	16,249	20,097
Expenses	(1,874)	(20,529)	(17,079)
Loss (income) from continuing operations of disposed properties before gain on disposition of properties	94	(4,280)	3,018
Gain on disposition of properties	5,140	48,886	81,965
Net income attributable to noncontrolling interests	(3,368)	(32,254)	(70,714)
Net income attributable to Acadia	$ 1,866	$ 12,352	$ 14,269

- Definition

Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. 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

- Definition

Amount after tax of income (loss) from a discontinued operation attributable to the noncontrolling interest. 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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=109222160&loc=d3e1012-107759

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-Subparagraph (a)
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+ Details

- 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 - Properties Held for Sale - Additional Information (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2017 USD ($) property	Sep. 30, 2017 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) property	Dec. 31, 2016 USD ($)
Long Lived Assets Held-for-sale [Line Items]
Impairment charges	$ 10,600	$ 3,800	$ 0	$ 14,455	$ 0
Fund II
Long Lived Assets Held-for-sale [Line Items]
Number of properties held-for-sale \| property	1			1
Properties held-for-sale	$ 25,400			$ 25,400
Date Sold			Apr. 17, 2018
Noncontrolling Interests
Long Lived Assets Held-for-sale [Line Items]
Impairment charges	$ 7,600	$ 2,700
Disposal group, held-for-sale
Long Lived Assets Held-for-sale [Line Items]
Properties held for sale net loss			$ 500	600
Impairment charges				10,600
Disposal group, held-for-sale \| Noncontrolling Interests
Long Lived Assets Held-for-sale [Line Items]
Impairment charges				$ 7,600

- Definition

+ References + Details

Real Estate - Schedule of Development in Process Activities (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) property	Dec. 31, 2017 USD ($) property
Property, Plant and Equipment [Line Items]
Number of properties under development \| property	3	5
Real estate under development	$ 120,297	$ 173,702
Transfers In	0
Capitalized Costs	45,867
Transfers Out	$ 99,272
Core Portfolio
Property, Plant and Equipment [Line Items]
Number of properties under development \| property	1	2
Real estate under development	$ 7,759	$ 21,897
Transfers In	0
Capitalized Costs	6,320
Transfers Out	$ 20,458
Fund Portfolio \| Fund II
Property, Plant and Equipment [Line Items]
Number of properties under development \| property	0	0
Real estate under development	$ 7,462	$ 4,908
Transfers In	0
Capitalized Costs	2,554
Transfers Out	$ 0
Fund Portfolio \| Fund III
Property, Plant and Equipment [Line Items]
Number of properties under development \| property	1	2
Real estate under development	$ 21,242	$ 63,939
Transfers In	0
Capitalized Costs	36,117
Transfers Out	$ 78,814
Fund Portfolio \| Fund IV
Property, Plant and Equipment [Line Items]
Number of properties under development \| property	1	1
Real estate under development	$ 83,834	$ 82,958
Transfers In	0
Capitalized Costs	876
Transfers Out	$ 0

Real Estate - Real Estate Under Development and Construction in Progress - Additional Information (Details) - property	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Number of unconsolidated project in development	1
Number of properties under development	3	5
Fund Portfolio \| Fund IV
Property, Plant and Equipment [Line Items]
Number of unconsolidated project in development		4
Number of projects put into service during period		3
Number of properties under development	1	1
Core Portfolio
Property, Plant and Equipment [Line Items]
Number of projects put into service during period	1	1
Number of properties under development	1	2

Notes Receivable, Net - Schedule of Notes Receivable (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) debtinstrument	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Net carrying amount of notes receivable \| $	$ 109,613	$ 153,829	$ 276,163	$ 147,188
Number of instruments held \| debtinstrument	5
Core Portfolio
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Net carrying amount of notes receivable \| $	$ 56,475	101,695
Number of instruments held \| debtinstrument	2
Core Portfolio \| Minimum
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Maturity Date	2019-04
Effective interest rate	6.00%
Core Portfolio \| Maximum
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Maturity Date	2020-04
Effective interest rate	8.10%
Fund Portfolio \| Fund II
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Net carrying amount of notes receivable \| $	$ 32,582	31,778
Number of instruments held \| debtinstrument	1
Maturity Date	2020-05
Effective interest rate	2.50%
Fund Portfolio \| Fund III
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Net carrying amount of notes receivable \| $	$ 5,306	5,106
Number of instruments held \| debtinstrument	1
Maturity Date	2020-07
Effective interest rate	18.00%
Fund Portfolio \| Fund IV
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Net carrying amount of notes receivable \| $	$ 15,250	$ 15,250
Number of instruments held \| debtinstrument	1
Maturity Date	2021-02
Effective interest rate	15.30%

Notes Receivable, Net - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Note receivable exchanged	$ 22,021	$ 101,705
Proceeds from notes receivable	26,000	32,000	$ 42,819
Additional advance	187,173	156,344	222,071
Recovered mortgage amount including accrued interest and fees		16,800
Notes receivable, net	109,613	153,829	$ 276,163	$ 147,188
Nonperforming Financial Instruments
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Proceeds from notes receivable		12,000
Fund III
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Additional advance	200	600
Fund II
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Note receivable accrued interest	800	800
Core Portfolio
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Note receivable accrued interest	200
Proceeds from notes receivable	26,000
Notes receivable, net	56,475	101,695
Core Portfolio \| Note Receivable Due April 1, 2020
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Proceeds from notes receivable	15,000
Additional advance	2,800
Core Portfolio \| Notes Receivable of $10 million
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Additional advance		10,000
Notes receivable, net		20,000
Core Portfolio \| Note Receivable, Due June 1, 2018
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Notes receivable, net		15,000
Town Center \| Core Portfolio
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Note receivable exchanged	22,000
Note receivable accrued interest	$ 300
Market Square and Town Center Properties \| Core Portfolio
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Note receivable exchanged		92,700
Note receivable accrued interest		1,800
Shopping Center in Windham, ME
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Note receivable exchanged		9,000
Note receivable accrued interest		$ 100

Investments in and Advances to Unconsolidated Affiliates - Schedule of Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Mar. 28, 2018	Dec. 31, 2017	Nov. 16, 2017
Schedule of Equity Method Investments [Line Items]
Due from related parties	$ (461)		$ 2,415
Other	556		556
Investments in and advances to unconsolidated affiliates	262,410		302,070
Distributions in excess of income from, and investments in, unconsolidated affiliates	$ 15,623		15,292
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	$ 21		167
Self Storage Management
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	95.00%
Equity method investments	$ 206		206
Fund III
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 227		373
Broughton St. Portfolio Savannah, GA
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	50.00%
Equity method investments	$ 3,236		48,335
Fund IV Other Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	90.00%
Equity method investments	$ 14,540		20,199
650 Bald Hill Road
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	90.00%
Equity method investments	$ 12,880		13,609
Fund IV
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 30,656		$ 82,143
Core Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	75.22%		61.11%	22.22%
Equity method investments	$ 231,432	$ 22,300	$ 216,583	$ 61,600
Core Portfolio \| 840 N. Michigan
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	88.43%
Equity method investments	$ 65,013		69,846
Core Portfolio \| Renaissance Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	20.00%
Equity method investments	$ 32,458		35,041
Core Portfolio \| Gotham Plaza
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	49.00%
Equity method investments	$ 29,550		29,416
Core Portfolio \| Town Center
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	75.22%
Equity method investments	$ 99,758		78,801
Core Portfolio \| Georgetown Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	50.00%
Equity method investments	$ 4,653		3,479
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	$ 15,623		$ 15,292

Investments in and Advances to Unconsolidated Affiliates - Schedule of Investments (Parenthetical) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
KLA Mervyns LLC
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 0	$ 0
Broughton St. Portfolio Savannah, GA
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 3,236	48,335
Cumulative capital contribution, percentage	15.00%
Cumulative capital contribution	$ 3,000	15,400
Preferred return percentage	9.00%
Preferred return	$ 2,800	$ 41,200

Investments in and Advances to Unconsolidated Affiliates - Core Portfolio - Additional Information (Details) $ in Thousands					1 Months Ended	12 Months Ended
	Mar. 28, 2018 USD ($)	Nov. 16, 2017 USD ($)	May 01, 2017 USD ($)	Jan. 04, 2017 USD ($) ft²	Apr. 29, 2016 USD ($)	Dec. 31, 2018 USD ($) ft² property	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Schedule of Equity Method Investments [Line Items]
Purchase Price						$ 186,463	$ 254,532
Note receivable exchanged						22,021	101,705
Notes receivable, net						109,613	153,829	$ 276,163	$ 147,188
Brandywine Portfolio
Schedule of Equity Method Investments [Line Items]
Preferred return						5,600
Core Portfolio
Schedule of Equity Method Investments [Line Items]
Purchase Price						1,337	42,800
Notes receivable, net						56,475	$ 101,695
Note receivable accrued interest						$ 200
Equity method investment, ownership percentage by third party	14.11%	38.89%				24.78%
Equity method investment, ownership percentage		22.22%				75.22%	61.11%
Equity method investments	$ 22,300	$ 61,600				$ 231,432	$ 216,583
Gain on equity method investment	12,700	34,500
Core Portfolio \| Renaissance Portfolio
Schedule of Equity Method Investments [Line Items]
Percentage of voting interests acquired				20.00%
Square footage of real estate property (in square feet) \| ft²						213,000
Number of businesses acquired \| property						18
Equity method investment, ownership percentage						20.00%
Equity method investments						$ 32,458	$ 35,041
Core Portfolio \| Brandywine Portfolio
Schedule of Equity Method Investments [Line Items]
Square footage of real estate property (in square feet) \| ft²						1,000,000
Repayments of debt					$ 140,000
Note receivable exchanged	22,000		$ 16,000
Notes receivable, net			153,400			$ 38,700
Note receivable accrued interest	$ 300		$ 300
Core Portfolio \| Brandywine Portfolio \| Exchange Transaction One
Schedule of Equity Method Investments [Line Items]
Note receivable exchanged		16,000
Note receivable accrued interest		600
Core Portfolio \| Brandywine Portfolio \| Exchange Transaction Two
Schedule of Equity Method Investments [Line Items]
Note receivable exchanged		60,700
Note receivable accrued interest		$ 900
Core Portfolio \| Market Square
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage by third party		38.89%	38.89%
Equity method investment, ownership percentage		22.22%	61.11%
Equity method investments			$ 16,300
Gain on equity method investment			$ 9,800
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

Investments in and Advances to Unconsolidated Affiliates - Fund Investments - Additional Information (Details)							1 Months Ended	3 Months Ended						12 Months Ended
	Aug. 29, 2018 USD ($) property	Jun. 29, 2018 USD ($) property	May 15, 2018 USD ($)	Jan. 18, 2018 USD ($) property	Jun. 30, 2017 USD ($)	Feb. 15, 2017 USD ($)	Jan. 31, 2017 USD ($)	Sep. 30, 2018 USD ($) property	Dec. 31, 2017 USD ($) property	Dec. 21, 2017 USD ($) property	Sep. 30, 2017 USD ($) property	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($) property	Dec. 31, 2018 USD ($) property segment	Dec. 31, 2017 USD ($) property	Dec. 31, 2016 USD ($)	Dec. 31, 2014 property JointVenture	Oct. 31, 2018
Schedule of Equity Method Investments [Line Items]
Cost method investments									$ 556,000					$ 556,000	$ 556,000
Equity in earnings (losses) of unconsolidated affiliates														$ 9,302,000	23,371,000	$ 39,449,000
Number of retail properties \| property														171
Proceeds from the disposition of properties, net														$ 63,866,000	260,711,000	150,378,000
Return of capital from unconsolidated affiliates and other														$ 26,338,000	$ 43,684,000	$ 79,030,000
Disposed of by sale
Schedule of Equity Method Investments [Line Items]
Number of retail properties \| property								2	3		2		2		3
Gain (loss) on disposal								$ 5,100,000	$ 35,900,000		$ 13,000,000	$ 3,300,000	$ 14,500,000
Partnership Interest \| Disposed of by sale
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal												800,000	$ 2,700,000
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]
Cost method investment ownership interest														1.05%
Distribution from cost method investment															2,400,000
Cost method investments									0						0
Equity in earnings (losses) of unconsolidated affiliates															2,000,000
Fund III's Storage Post venture
Schedule of Equity Method Investments [Line Items]
Distribution from cost method investment			$ 3,200,000
Cost method investments			0
Fund III's Storage Post venture \| Partnership Interest
Schedule of Equity Method Investments [Line Items]
Distribution from cost method investment			$ 800,000
BSP I and BSP II
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage																	50.00%
Number of Joint Ventures \| JointVenture																	2
Broughton St. Portfolio Savannah, GA
Schedule of Equity Method Investments [Line Items]
Equity method investments									48,335,000					$ 3,236,000	48,335,000
Equity method investment, ownership percentage														50.00%
Number of businesses acquired \| property																	23
Number of retail properties \| property														13
Fund I Vs Broughton Street Portfolio Venture
Schedule of Equity Method Investments [Line Items]
Number of retail properties \| property		2															8
Losses on cost method investments		$ 1,000,000
Fund I Vs Broughton Street Portfolio Venture \| Partnership Interest \| Maximum
Schedule of Equity Method Investments [Line Items]
Losses on cost method investments		$ 100,000
Fund IV
Schedule of Equity Method Investments [Line Items]
Equity method investments									82,143,000					$ 30,656,000	82,143,000
Fund IV \| Disposed of by sale \| Broughton St. Portfolio Savannah, GA
Schedule of Equity Method Investments [Line Items]
Number of retail properties \| property	1			2						5							2
Proceeds from the disposition of properties, net	$ 2,000,000			$ 8,000,000
Gain (loss) on disposal	(300,000)			(400,000)						$ 1,200,000
Return of capital from unconsolidated affiliates and other										11,000,000
Fund IV \| Disposed of by sale \| 2819 Kennedy Boulevard
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal							$ 6,300,000
Consideration received							19,000,000
Return of capital from unconsolidated affiliates and other							10,600,000
Fund IV \| Disposed of by sale \| 2819 Kennedy Boulevard \| Mortgages
Schedule of Equity Method Investments [Line Items]
Repayments of debt							8,400,000
Fund IV \| Disposed of by sale \| 1701 Belmont Avenue
Schedule of Equity Method Investments [Line Items]
Consideration received					$ 5,600,000							$ 5,600,000
Return of capital from unconsolidated affiliates and other					2,700,000
Fund IV \| Disposed of by sale \| 1701 Belmont Avenue \| Mortgages
Schedule of Equity Method Investments [Line Items]
Repayments of debt					2,900,000
Fund IV \| Partnership Interest \| Disposed of by sale \| Broughton St. Portfolio Savannah, GA
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal				$ 0						100,000
Fund IV \| Partnership Interest \| Disposed of by sale \| Broughton St. Portfolio Savannah, GA \| Maximum
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal	$ (100,000)
Fund IV \| Partnership Interest \| Disposed of by sale \| 2819 Kennedy Boulevard
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal							1,400,000
Fund IV \| Consolidated Entity \| Disposed of by sale \| Broughton St. Portfolio Savannah, GA
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal										$ 600,000
Fund IV \| Consolidated Entity \| Disposed of by sale \| 2819 Kennedy Boulevard
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal							$ 6,200,000
Fund IV \| Consolidated Entity \| Disposed of by sale \| 1701 Belmont Avenue
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal					$ 3,300,000
BSP I
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage																		100.00%
BSP I \| Consolidated Entity
Schedule of Equity Method Investments [Line Items]
Number of retail properties \| segment														11
BSP II \| Unconsolidated Affiliates
Schedule of Equity Method Investments [Line Items]
Number of retail properties \| property														2
Fund III
Schedule of Equity Method Investments [Line Items]
Equity method investments									$ 373,000					$ 227,000	$ 373,000
Fund III \| Disposed of by sale \| Arundel Plaza
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal						$ 8,200,000
Consideration received						28,800,000
Return of capital from unconsolidated affiliates and other						18,800,000
Fund III \| Disposed of by sale \| Arundel Plaza \| Mortgages
Schedule of Equity Method Investments [Line Items]
Repayments of debt						10,000,000
Fund III \| Partnership Interest \| Disposed of by sale \| Arundel Plaza
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal						1,300,000
Fund III \| Consolidated Entity \| Disposed of by sale \| Arundel Plaza
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal						$ 5,300,000

Investments in and Advances to Unconsolidated Affiliates - Unconsolidated Affiliates - Additional Information (Details) - Equity Method Investee - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Schedule of Equity Method Investments [Line Items]
Related party revenue	$ 1.1	$ 1.3	$ 1.2
Expenses, related party	$ 2.2	$ 2.0	$ 2.4

Investments in and Advances to Unconsolidated Affiliates - Unconsolidated Affiliates - Schedule of Condensed Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Combined and Condensed Balance Sheets
Real estate under development	$ 120,297	$ 173,702
Other assets	208,570	214,959
Total assets	3,958,780	3,960,247	$ 3,995,960
Total liabilities and equity	3,958,780	3,960,247
Company's share of distributions in excess of income from and investments in unconsolidated affiliates	15,623	15,292
Investments in and advances to unconsolidated affiliates	262,410	302,070
Unconsolidated Affiliates
Combined and Condensed Balance Sheets
Rental property, net	488,000	518,900
Real estate under development		26,681
Investment in unconsolidated affiliates	6,853	6,853
Other assets	91,497	100,901
Total assets	586,350	653,335
Mortgage notes payable	408,967	405,652
Other liabilities	54,675	61,932
Partners’ equity	122,708	185,751
Total liabilities and equity	586,350	653,335
Company's share of accumulated equity	141,384	185,533
Basis differential	104,084	95,358
Deferred fees, net of portion related to the Company's interest	1,780	3,472
Amounts (payable) receivable by the Company	(461)	2,415
Investments in and advances to unconsolidated affiliates, net of Company's share of distributions in excess of income from and investments in unconsolidated affiliates	246,787	286,778
Company's share of distributions in excess of income from and investments in unconsolidated affiliates	15,623	15,292
Investments in and advances to unconsolidated affiliates	$ 262,410	$ 302,070

Investments in and Advances to Unconsolidated Affiliates - Unconsolidated Affiliates - Schedule of Condensed Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Combined and Condensed Statements of Income
Revenues	$ 69,445	$ 66,075	$ 63,569	$ 63,124	$ 66,081	$ 62,678	$ 59,504	$ 61,999	$ 262,213	$ 250,262	$ 189,939
Operating and other expenses									(234,672)	(232,943)	(168,050)
Depreciation and amortization									(117,549)	(104,934)	(70,011)
(Loss) income from continuing operations before gain on disposition of properties									(20,838)	15,422	52,627
Company’s equity in earnings of unconsolidated affiliates									9,302	23,371	39,449
Unconsolidated Affiliates
Combined and Condensed Statements of Income
Revenues									80,184	83,222	84,218
Operating and other expenses									(23,586)	(24,711)	(25,724)
Interest expense									(19,954)	(18,733)	(16,300)
Depreciation and amortization									(22,228)	(24,192)	(35,432)
Loss on debt extinguishment										(154)
(Loss) gain on disposition of properties									(1,673)	18,957	(1,340)
(Loss) income from continuing operations before gain on disposition of properties									12,743	34,389	5,422
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									12,345	26,039	40,538
Basis differential amortization									(3,043)	(2,668)	(1,089)
Company’s equity in earnings of unconsolidated affiliates									$ 9,302	$ 23,371	$ 39,449

Other Assets, Net and Accounts Payable and Other Liabilities - Schedule of other assets and other liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Other Assets, Net:
Lease intangibles, net (Note 6)	$ 115,939	$ 127,571
Deferred charges, net	28,619	24,589
Prepaid expenses	18,422	16,838
Other receivables	5,058	11,356
Accrued interest receivable	17,046	11,668
Deposits	4,611	6,296
Due from seller	4,000	4,300
Deferred tax assets	2,032	2,096
Derivative financial instruments (Note 8)	7,018	4,402
Due from related parties	1,802	1,479
Corporate assets	1,953	2,369
Income taxes receivable	2,070	1,995
Other assets, net	208,570	214,959
Deferred Charges, Net:
Deferred leasing and other costs	45,011	41,020
Deferred financing costs related to line of credit	8,960	7,786
Deferred costs, gross	53,971	48,806
Accumulated amortization	(25,352)	(24,217)
Deferred charges, net	28,619	24,589
Accounts Payable and Other Liabilities:
Lease intangibles, net (Note 6)	95,045	104,478
Accounts payable and accrued expenses	65,215	61,420
Deferred income	34,052	31,306
Tenant security deposits, escrow and other	10,588	10,029
Derivative financial instruments (Note 8)	7,304	1,467
Income taxes payable	19	176
Other	2,738	1,176
Accounts payable and other liabilities	$ 214,961	$ 210,052

Lease Intangibles - Schedule of Intangible Assets and Liabilities Included in Other Assets and Other Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Amortizable Intangible Assets, Gross Carrying Amount	$ 234,190	$ 210,607
Amortizable Intangible Assets, Accumulated Amortization	(118,251)	(83,036)
Amortizable Intangible Assets, Net Carrying Amount	115,939	127,571
Amortizable Intangible Liabilities
Amortizable Intangible Liabilities, Gross Carrying Amount	(152,188)	(147,232)
Amortizable Intangible Liabilities, Accumulated Amortization	57,721	43,391
Amortizable Intangible Liabilities, Net Carrying Amount	(94,467)	(103,841)
Above-market Ground Lease, Gross	(671)	(671)
Above-market Ground Lease, Accumulated Amortization	93	34
Above-market Ground Lease, Net	(578)	(637)
Finite-Lived Intangible Liabilities, Gross	(152,859)	(147,903)
Finite-Lived Intangible Liabilities, Accumulated Amortization	57,814	43,425
Finite-Lived Intangible Liabilities, Net	(95,045)	(104,478)
In-place lease intangible assets
Finite-Lived Intangible Assets [Line Items]
Amortizable Intangible Assets, Gross Carrying Amount	216,021	193,821
Amortizable Intangible Assets, Accumulated Amortization	(105,972)	(72,749)
Amortizable Intangible Assets, Net Carrying Amount	110,049	121,072
Amortizable Intangible Liabilities
Amortizable Intangible Liabilities, Net Carrying Amount	(88,577)
Above-market rent
Finite-Lived Intangible Assets [Line Items]
Amortizable Intangible Assets, Gross Carrying Amount	18,169	16,786
Amortizable Intangible Assets, Accumulated Amortization	(12,279)	(10,287)
Amortizable Intangible Assets, Net Carrying Amount	$ 5,890	$ 6,499

Lease Intangibles - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Below market rents, acquired	$ 7.9	$ 10.9
Below market rents acquired, weighted average useful life	20 years 6 months	12 years 1 month 6 days
Above-market ground lease, acquired		$ 0.7
Above-market ground lease acquired, weighted average useful life		11 years 6 months
In-place lease intangible assets
Finite-Lived Intangible Assets [Line Items]
Intangible assets acquired	$ 24.2	$ 41.6
Acquired intangible assets, weighted average useful life	4 years 3 months 18 days	4 years 1 month 6 days
Above-market rent
Finite-Lived Intangible Assets [Line Items]
Intangible assets acquired	$ 2.5	$ 2.7
Acquired intangible assets, weighted average useful life	1 year 8 months 12 days	4 years 9 months 18 days

Lease Intangibles - Scheduled Amortization of Acquired Lease Intangible Assets and Assumed Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Acquired Lease Intangibles [Abstract]
Net Increase In Lease Revenues, Total	$ 94,467	$ 103,841
Amortizable Intangible Assets, Net Carrying Amount	(115,939)	(127,571)
In-place lease intangible assets
Acquired Lease Intangibles [Abstract]
2019, Net Increase In Lease Revenues	8,431
2020, Net Increase In Lease Revenues	8,206
2021, Net Increase In Lease Revenues	7,725
2022, Net Increase In Lease Revenues	7,346
2023, Net Increase In Lease Revenues	7,053
Thereafter, Net Increase In Lease Revenues	49,816
Net Increase In Lease Revenues, Total	88,577
2019, Increase to Amortization	(27,309)
2020, Increase to Amortization	(20,511)
2021, Increase to Amortization	(15,196)
2022, Increase to Amortization	(10,467)
2023, Increase to Amortization	(8,192)
Thereafter, Increase to Amortization	(28,374)
Amortizable Intangible Assets, Net Carrying Amount	(110,049)	$ (121,072)
2019, Reduction of Rent Expense	58
2020, Reduction of Rent Expense	58
2021, Reduction of Rent Expense	58
2022, Reduction of Rent Expense	58
2023, Reduction of Rent Expense	58
Thereafter, Reduction of Rent Expense	288
Reduction of Rent Expense, Total	578
2019, Net Income (Expense)	(18,820)
2020, Net Income (Expense)	(12,247)
2021, Net Income (Expense)	(7,413)
2022, Net Income (Expense)	(3,063)
2023, Net Income (Expense)	(1,081)
Thereafter, Net Income (Expense)	21,730
Total, Net Income (Expense)	$ (20,894)

Debt - Summary of Consolidated Indebtedness (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term debt, gross	$ 1,560,333	$ 1,438,386
Net unamortized debt issuance costs	(10,541)	(14,833)
Unamortized fair market value of assumed debt	753	856
Mortgage and other notes payable, net	1,017,288	909,174
Unsecured notes payable, net	533,257	473,735
Unsecured line of credit	0	41,500
Total Indebtedness	1,550,545	1,424,409
Fixed Rate
Debt Instrument [Line Items]
Long-term debt, gross	1,001,658	899,650
Total Debt - Variable Rate
Debt Instrument [Line Items]
Long-term debt, gross	558,675	538,736
Mortgages
Debt Instrument [Line Items]
Net unamortized debt issuance costs	(10,173)	(12,943)
Unamortized fair market value of assumed debt	753	856
Mortgage and other notes payable, net	1,017,288	909,174
Unsecured Debt
Debt Instrument [Line Items]
Net unamortized debt issuance costs	(368)	(1,890)
Unsecured notes payable, net	$ 533,257	473,735
Line of Credit
Debt Instrument [Line Items]
Unsecured line of credit		41,500
Core Portfolio \| Minimum
Debt Instrument [Line Items]
Maturity Date	2019-04
Core Portfolio \| Maximum
Debt Instrument [Line Items]
Maturity Date	2020-04
Core Portfolio \| Variable Rate Debt \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.70%
Core Portfolio \| Variable Rate Debt \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	1.90%
Core Portfolio \| Unsecured Line of Credit \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.35%
Core Portfolio \| Unsecured Notes Payable \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.25%
Core Portfolio \| Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	$ 260,854	254,022
Core Portfolio \| Mortgages \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.65%
Core Portfolio \| Mortgages \| Fixed Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 178,271	$ 179,870
Core Portfolio \| Mortgages \| Fixed Rate \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	3.88%	3.88%
Maturity Date	2024-02
Core Portfolio \| Mortgages \| Fixed Rate \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	6.00%	5.89%
Maturity Date	2035-04
Core Portfolio \| Mortgages \| Variable Rate - Swapped
Debt Instrument [Line Items]
Long-term debt, gross	$ 82,583	$ 74,152
Core Portfolio \| Mortgages \| Variable Rate - Swapped \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	3.41%	3.41%
Maturity Date	2023-01
Core Portfolio \| Mortgages \| Variable Rate - Swapped \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	5.67%	5.67%
Maturity Date	2026-06
Core Portfolio \| Unsecured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 350,000	$ 300,000
Core Portfolio \| Unsecured Debt \| Variable Rate Unsecured Term Loans - Swapped
Debt Instrument [Line Items]
Maturity Date	2023-03
Long-term debt, gross	$ 349,617	$ 300,000
Core Portfolio \| Unsecured Debt \| Variable Rate Unsecured Term Loans - Swapped \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	2.49%	2.54%
Core Portfolio \| Unsecured Debt \| Variable Rate Unsecured Term Loans - Swapped \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	4.05%	3.59%
Core Portfolio \| Unsecured Debt \| Term Loans
Debt Instrument [Line Items]
Long-term debt, gross	$ 383
Core Portfolio \| Unsecured Debt \| Term Loans \| LIBOR
Debt Instrument [Line Items]
Interest rate, stated percentage	1.25%
Maturity Date	2023-03
Core Portfolio \| Line of Credit \| Unsecured Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross	$ 0	$ 18,048
Core Portfolio \| Line of Credit \| Unsecured Line of Credit \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.35%	1.40%
Maturity Date	2022-03
Core Portfolio \| Line of Credit \| Unsecured Line of Credit - Swapped
Debt Instrument [Line Items]
Maturity Date	2022-03
Long-term debt, gross		$ 23,452
Core Portfolio \| Line of Credit \| Unsecured Line of Credit - Swapped \| LIBOR \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	4.15%	4.20%
Core Portfolio \| Line of Credit \| Unsecured Line of Credit - Swapped \| LIBOR \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	5.02%	5.07%
Fund II \| Fund Portfolio
Debt Instrument [Line Items]
Maturity Date	2020-05
Fund II \| Fund Portfolio \| Variable Rate Debt \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.39%
Fund II \| Fund Portfolio \| Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	$ 224,587	$ 224,822
Fund II \| Fund Portfolio \| Mortgages \| Fixed Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 205,262	$ 205,262
Fund II \| Fund Portfolio \| Mortgages \| Fixed Rate \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	1.00%	1.00%
Maturity Date	2020-05
Fund II \| Fund Portfolio \| Mortgages \| Fixed Rate \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	4.75%	4.75%
Maturity Date	2042-08
Fund II \| Fund Portfolio \| Mortgages \| Variable Rate - Swapped
Debt Instrument [Line Items]
Interest rate, stated percentage	4.27%	4.27%
Maturity Date	2021-11
Long-term debt, gross	$ 19,325	$ 19,560
Fund II \| Fund Portfolio \| Unsecured Debt \| Variable Rate Debt \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.65%	1.40%
Fund II \| Fund Portfolio \| Unsecured Debt \| Unsecured Notes Payable
Debt Instrument [Line Items]
Long-term debt, gross	$ 40,000	$ 31,500
Fund II \| Fund Portfolio \| Unsecured Debt \| Unsecured Notes Payable \| LIBOR
Debt Instrument [Line Items]
Maturity Date	2020-09
Fund III \| Fund Portfolio
Debt Instrument [Line Items]
Maturity Date	2020-07
Fund III \| Fund Portfolio \| Variable Rate Debt \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	2.65%
Fund III \| Fund Portfolio \| Variable Rate Debt \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	4.65%
Fund III \| Fund Portfolio \| Mortgages \| Variable Rate Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 90,096	$ 65,866
Fund III \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	2.65%
Maturity Date	2020-06
Fund III \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	4.65%	4.65%
Maturity Date	2021-12
Fund III \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| Prime Rate \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate		0.50%
Fund IV \| Fund Portfolio
Debt Instrument [Line Items]
Maturity Date	2021-02
Fund IV \| Fund Portfolio \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.60%
Fund IV \| Fund Portfolio \| 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	$ 313,095	$ 347,938
Fund IV \| Fund Portfolio \| Mortgages \| Fixed Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 8,189	$ 10,503
Fund IV \| Fund Portfolio \| Mortgages \| Fixed Rate \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	3.40%	3.40%
Maturity Date	2025-10
Fund IV \| Fund Portfolio \| Mortgages \| Fixed Rate \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	4.50%	4.50%
Maturity Date	2026-06
Fund IV \| Fund Portfolio \| Mortgages \| Variable Rate - Swapped
Debt Instrument [Line Items]
Long-term debt, gross	$ 71,841	$ 86,851
Fund IV \| Fund Portfolio \| Mortgages \| Variable Rate - Swapped \| Minimum
Debt Instrument [Line Items]
Maturity Date	2019-05
Fund IV \| Fund Portfolio \| Mortgages \| Variable Rate - Swapped \| Maximum
Debt Instrument [Line Items]
Maturity Date	2022-12
Fund IV \| Fund Portfolio \| Mortgages \| Variable Rate - Swapped \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	3.67%	3.67%
Fund IV \| Fund Portfolio \| Mortgages \| Variable Rate - Swapped \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	4.23%	4.23%
Fund IV \| Fund Portfolio \| Mortgages \| Variable Rate Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 233,065	$ 250,584
Fund IV \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.60%	1.70%
Maturity Date	2019-02
Fund IV \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	3.95%	3.95%
Maturity Date	2021-08
Fund IV \| Fund Portfolio \| Unsecured Debt \| Term Loan / Subscription Facility
Debt Instrument [Line Items]
Long-term debt, gross	$ 40,825	$ 40,825
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%
Maturity Date	2019-10
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%
Maturity Date	2019-12
Fund V \| Fund Portfolio \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	2.15%
Fund V \| Fund Portfolio \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Fund V \| Fund Portfolio \| Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	$ 138,076	$ 28,613
Fund V \| Fund Portfolio \| Mortgages \| Variable Rate - Swapped
Debt Instrument [Line Items]
Long-term debt, gross	$ 86,570	0
Fund V \| Fund Portfolio \| Mortgages \| Variable Rate - Swapped \| Minimum
Debt Instrument [Line Items]
Maturity Date	2021-02
Fund V \| Fund Portfolio \| Mortgages \| Variable Rate - Swapped \| Maximum
Debt Instrument [Line Items]
Maturity Date	2021-06
Fund V \| Fund Portfolio \| Mortgages \| Variable Rate - Swapped \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	4.61%
Fund V \| Fund Portfolio \| Mortgages \| Variable Rate - Swapped \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	4.78%
Fund V \| Fund Portfolio \| Mortgages \| Variable Rate Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 51,506	$ 28,613
Fund V \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		2.25%
Fund V \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	2.15%
Maturity Date	2020-10
Fund V \| Fund Portfolio \| Mortgages \| Variable Rate Debt \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Maturity Date	2021-01
Fund V \| Fund Portfolio \| Unsecured Debt \| Subscription Line
Debt Instrument [Line Items]
Long-term debt, gross	$ 102,800	$ 103,300
Fund V \| Fund Portfolio \| Unsecured Debt \| Subscription Line \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.60%	1.60%
Maturity Date	2020-05

Debt - Summary of Consolidated Indebtedness (Parenthetical) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term debt, gross	$ 1,560,333	$ 1,438,386
Variable-rate debt that subject to interest cap agreements
Debt Instrument [Line Items]
Long-term debt, gross	143,800	141,100
Total Debt - Variable Rate Debt Fixed with Interest Rate Swap Agreements
Debt Instrument [Line Items]
Long-term debt, gross	$ 609,900	$ 504,000
Minimum \| Core Portfolio \| Variable Rate Debt \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.70%
Minimum \| Core Portfolio \| Unsecured Notes Payable \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.25%
Minimum \| Core Portfolio \| Unsecured Line of Credit \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.35%
Maximum \| Core Portfolio \| Variable Rate Debt \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.90%
Fund II \| Fund Portfolio \| Variable Rate Debt \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.39%
Fund III \| Minimum \| Fund Portfolio \| Variable Rate Debt \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.65%
Fund III \| Maximum \| Fund Portfolio \| Variable Rate Debt \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	4.65%
Fund IV \| Minimum \| Fund Portfolio \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.60%
Fund IV \| Maximum \| Fund Portfolio \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	3.95%
Fund V \| Minimum \| Fund Portfolio \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.15%
Fund V \| Maximum \| Fund Portfolio \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%

Debt - Credit Facility - Additional Information (Details) - USD ($)	Feb. 20, 2018	Dec. 31, 2018
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 300,000,000
Unsecured Debt
Debt Instrument [Line Items]
Maturity date	Mar. 31, 2023
Unsecured Debt \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 150,000,000
Basis spread on variable rate	1.35%
Maturity date	Mar. 31, 2022
Unsecured Debt \| Senior Unsecured Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 500,000,000
Unsecured Debt \| $300 Million Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 350,000,000
Basis spread on variable rate	1.25%
Unsecured Debt \| $150 Million Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 150,000,000
Other Secured Financings
Debt Instrument [Line Items]
Maximum borrowing capacity	40,400,000
Core Portfolio \| Unsecured Debt \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	150,000,000	$ 150,000,000
Core Portfolio \| Unsecured Debt \| $150 Million Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 150,000,000

Debt - Mortgage Payable - Additional Information (Details)	12 Months Ended
	Dec. 31, 2018 USD ($) property loan derivative	Dec. 31, 2017 USD ($) property
Debt Instrument [Line Items]
Amount drawn on loan	$ 1,017,288,000	$ 909,174,000
Derivative, notional amount	69,670,000
Unsecured line of credit	0	41,500,000
Mortgages
Debt Instrument [Line Items]
Amount drawn on loan	$ 1,017,288,000	$ 909,174,000
Number of properties collateralized \| property	43	42
Interest Rate Swaps
Debt Instrument [Line Items]
Derivative, notional amount	$ 50,000,000
Derivative fixed interest rate	2.80%
Interest Rate Swaps \| Mortgages
Debt Instrument [Line Items]
Number of interest rate derivatives held \| derivative	4
Derivative, notional amount	$ 136,600,000
Derivative fixed interest rate	2.86%
Fund V \| Mortgages
Debt Instrument [Line Items]
Number of mortgage loans \| loan	4
Borrowings, amount	$ 109,500,000
Core Portfolio
Debt Instrument [Line Items]
Derivative, notional amount	432,200,000
Core Portfolio \| Maturing In 2028
Debt Instrument [Line Items]
Amount drawn on loan	$ 50,000,000
Core Portfolio \| Mortgages
Debt Instrument [Line Items]
Number of notes repaid \| loan	1
Repayments of debt	$ 40,400,000
Scheduled principal payment	6,700,000
Core Portfolio \| Mortgages \| Brandywine Portfolio
Debt Instrument [Line Items]
Debt default, amount	$ 26,300,000	$ 26,300,000
Interest rate, stated percentage	6.00%
Debt default interest	5.00%
Interest owner percentage in property	22.00%
Core Portfolio \| Mortgages \| Maturing In 2028
Debt Instrument [Line Items]
Borrowings, amount	$ 73,500,000
Fund III \| Construction Loans
Debt Instrument [Line Items]
Unsecured line of credit	$ 24,600,000
Fund IV \| Mortgages
Debt Instrument [Line Items]
Number of notes repaid \| loan	3
Fund IV \| Mortgages One
Debt Instrument [Line Items]
Repayments of debt	$ 27,200,000
LIBOR \| Fund V \| Mortgages
Debt Instrument [Line Items]
Basis spread on variable rate	1.99%
LIBOR \| Core Portfolio \| Mortgages
Debt Instrument [Line Items]
Basis spread on variable rate	1.65%
LIBOR \| Core Portfolio \| Mortgages \| Maturing In 2028
Debt Instrument [Line Items]
Basis spread on variable rate	1.50%
LIBOR \| Fund IV \| Mortgages One
Debt Instrument [Line Items]
Basis spread on variable rate	2.81%

Debt - Unsecured Notes Payable - Additional Information (Details) - USD ($)		12 Months Ended
	Feb. 20, 2018	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 300,000,000
Long-term debt outstanding		$ 1,560,333,000	$ 1,438,386,000
Derivative, notional amount		69,670,000
Letters of credit, outstanding amount		19,700,000	19,700,000
Core Portfolio
Debt Instrument [Line Items]
Derivative, notional amount		432,200,000
Fund Portfolio \| Fund II
Debt Instrument [Line Items]
Derivative, notional amount		19,325,000
Fund Portfolio \| Fund IV
Debt Instrument [Line Items]
Derivative, notional amount		180,741,000
Fund Portfolio \| Fund V
Debt Instrument [Line Items]
Derivative, notional amount		86,570,000
Interest Rate Swaps
Debt Instrument [Line Items]
Derivative, notional amount		$ 50,000,000
Derivative fixed interest rate		2.80%
Unsecured Debt \| Fund IV \| Letter of Credit
Debt Instrument [Line Items]
Letters of credit, outstanding amount		$ 7,400,000	7,400,000
Unsecured Debt \| Core Portfolio
Debt Instrument [Line Items]
Long-term debt outstanding		350,000,000	300,000,000
Unsecured Notes Payable \| Unsecured Debt
Debt Instrument [Line Items]
Debt available balance		62,300,000	70,300,000
Unsecured Notes Payable \| Unsecured Debt \| Fund Portfolio \| Fund II
Debt Instrument [Line Items]
Long-term debt outstanding		40,000,000	31,500,000
$300 Million Term Loan \| Unsecured Debt \| Core Portfolio
Debt Instrument [Line Items]
Maximum borrowing capacity	300,000,000
$350 Million Term Loan \| Unsecured Debt \| Core Portfolio
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 350,000,000
Long-term debt outstanding		350,000,000	300,000,000
$350 Million Term Loan \| Unsecured Debt \| Core Portfolio \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.25%
Term Loan Maturing In September 2020 \| Secured Debt \| Fund II
Debt Instrument [Line Items]
Maximum borrowing capacity		40,000,000
Long-term line of credit, noncurrent		40,000,000	31,500,000
Remaining borrowing capacity		0	8,500,000
Bridge facility \| Unsecured Debt \| Fund IV
Debt Instrument [Line Items]
Maximum borrowing capacity		41,800,000
Long-term line of credit, noncurrent		40,800,000	40,800,000
Remaining borrowing capacity		1,000,000	1,000,000
Subscription Line \| Unsecured Debt \| Fund IV
Debt Instrument [Line Items]
Maximum borrowing capacity		21,500,000
Long-term line of credit, noncurrent		0	0
Remaining borrowing capacity		14,100,000	14,100,000
Subscription Line \| Unsecured Debt \| Fund V
Debt Instrument [Line Items]
Maximum borrowing capacity		150,000,000
Long-term line of credit, noncurrent		102,800,000
Remaining borrowing capacity		47,200,000
Subscription Line \| Unsecured Debt \| Fund Portfolio \| Fund V
Debt Instrument [Line Items]
Long-term debt outstanding		$ 102,800,000	103,300,000
Remaining borrowing capacity			$ 46,700,000
Subscription Line \| Unsecured Debt \| Fund Portfolio \| LIBOR \| Fund V
Debt Instrument [Line Items]
Basis spread on variable rate		1.60%	1.60%

Debt - Unsecured Revolving Lines of Credit - Additional Information (Details) - USD ($)	Dec. 31, 2018	Feb. 20, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 300,000,000
Letters of credit, outstanding amount	$ 19,700,000		$ 19,700,000
Revolving Credit Facility \| Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity		150,000,000
Core Portfolio \| Revolving Credit Facility \| Unsecured Debt
Debt Instrument [Line Items]
Debt available balance	137,700,000		96,200,000
Maximum borrowing capacity	150,000,000	$ 150,000,000
Credit facility amount outstanding	0		41,500,000
Letters of credit, outstanding amount	$ 12,300,000		$ 12,300,000

Debt - Scheduled Principal Repayments (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
2019	$ 219,118
2020	527,304
2021	180,511
2022	48,528
2023	370,680
Thereafter	214,192
Long-term debt and convertible notes payable	1,560,333	$ 1,438,386
Unamortized premium	753	856
Net unamortized debt issuance costs	(10,541)	(14,833)
Total Indebtedness	$ 1,550,545	$ 1,424,409

Financial Instruments and Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Assets
Derivative financial instruments	$ 7,018	$ 4,402
Liabilities
Derivative financial instruments	7,304	1,467
Recurring \| Level 1
Assets
Money Market Funds	4,504	3
Derivative financial instruments	0	0
Liabilities
Derivative financial instruments	0	0
Recurring \| Level 2
Assets
Money Market Funds	0	0
Derivative financial instruments	7,018	4,402
Liabilities
Derivative financial instruments	7,304	1,467
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 ($)	3 Months Ended		12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges	$ 10,600,000	$ 3,800,000	$ 0	$ 14,455,000	$ 0
Reclassification adjustment related to derivatives from AOCI to interest expense			2,300,000
Derivatives designated as fair value hedges	0		0	0
Derivative designated to hedges of net investments in foreign operations	0		$ 0	0
Noncontrolling Interests
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges	$ 7,600,000	$ 2,700,000
Disposal group, held-for-sale
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges				10,600,000
Disposal group, held-for-sale \| Noncontrolling Interests
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges				7,600,000
Nonrecurring \| Disposal group, held-for-sale \| Property Classified As Held For Sale At September 30, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges				3,800,000
Nonrecurring \| Disposal group, held-for-sale \| Property Classified As Held For Sale At December 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges				10,600,000
Nonrecurring \| Disposal group, held-for-sale \| Noncontrolling Interests \| Property Classified As Held For Sale At September 30, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges				2,700,000
Nonrecurring \| Disposal group, held-for-sale \| Noncontrolling Interests \| Property Classified As Held For Sale At December 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges				$ 7,600,000

Financial Instruments and Fair Value Measurements - Schedule of Derivative Financial Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Jul. 31, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 69,670
Derivative Effective Date	2018-06
Fair value, liability derivatives	$ (7,304)		$ (1,467)
Fair value, asset derivatives	$ 7,018		4,402
Minimum
Derivatives, Fair Value [Line Items]
Derivative Maturity Date	2021-06
Strike Rate	2.78%
Maximum
Derivatives, Fair Value [Line Items]
Derivative Maturity Date	2023-06
Strike Rate	2.88%
Interest Rate Swaps
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 50,000
Derivative Effective Date	2020-07
Fair value, liability derivatives		$ (2,900)
Core Portfolio
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 432,200
Fair value, derivatives, net	(310)		2,638
Core Portfolio \| Interest Rate Swaps \| Other Liabilities
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	111,117
Fair value, liability derivatives	(6,332)		(1,438)
Core Portfolio \| Interest Rate Swaps \| Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	321,083
Fair value, asset derivatives	$ 6,022		4,076
Core Portfolio \| Interest Rate Swaps \| Minimum \| Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative Effective Date	2012-12
Derivative Maturity Date	2022-12
Strike Rate	2.80%
Core Portfolio \| Interest Rate Swaps \| Minimum \| Other Assets
Derivatives, Fair Value [Line Items]
Derivative Effective Date	2013-02
Derivative Maturity Date	2019-11
Strike Rate	1.24%
Core Portfolio \| Interest Rate Swaps \| Maximum \| Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative Effective Date	2020-07
Derivative Maturity Date	2030-07
Strike Rate	3.77%
Core Portfolio \| Interest Rate Swaps \| Maximum \| Other Assets
Derivatives, Fair Value [Line Items]
Derivative Effective Date	2017-12
Derivative Maturity Date	2027-07
Strike Rate	3.77%
Fund Portfolio \| Fund II
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 19,325
Fair value, derivatives, net	108		(29)
Fund Portfolio \| Fund II \| Interest Rate Swaps \| Other Liabilities
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 0
Derivative Effective Date	2014-10
Derivative Maturity Date	2021-11
Fair value, liability derivatives	$ 0		(29)
Fund Portfolio \| Fund II \| Interest Rate Swaps \| Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 19,325
Derivative Effective Date	2014-10
Derivative Maturity Date	2021-11
Fair value, asset derivatives	$ 108		0
Fund Portfolio \| Fund II \| Interest Rate Swaps \| Minimum \| Other Liabilities
Derivatives, Fair Value [Line Items]
Strike Rate	2.88%
Fund Portfolio \| Fund II \| Interest Rate Swaps \| Minimum \| Other Assets
Derivatives, Fair Value [Line Items]
Strike Rate	2.88%
Fund Portfolio \| Fund II \| Interest Rate Swaps \| Maximum \| Other Liabilities
Derivatives, Fair Value [Line Items]
Strike Rate	2.88%
Fund Portfolio \| Fund II \| Interest Rate Swaps \| Maximum \| Other Assets
Derivatives, Fair Value [Line Items]
Strike Rate	2.88%
Fund Portfolio \| Fund III \| Interest Rate Cap \| Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 58,000
Derivative Effective Date	2016-12
Derivative Maturity Date	2020-01
Fair value, asset derivatives	$ 8		14
Fund Portfolio \| Fund III \| Interest Rate Cap \| Minimum \| Other Assets
Derivatives, Fair Value [Line Items]
Strike Rate	3.00%
Fund Portfolio \| Fund III \| Interest Rate Cap \| Maximum \| Other Assets
Derivatives, Fair Value [Line Items]
Strike Rate	3.00%
Fund Portfolio \| Fund IV
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 180,741
Fair value, derivatives, net	859		312
Fund Portfolio \| Fund IV \| Interest Rate Swaps \| Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	71,841
Fair value, asset derivatives	$ 851		295
Fund Portfolio \| Fund IV \| Interest Rate Swaps \| Minimum \| Other Assets
Derivatives, Fair Value [Line Items]
Derivative Effective Date	2017-03
Derivative Maturity Date	2020-03
Strike Rate	1.82%
Fund Portfolio \| Fund IV \| Interest Rate Swaps \| Maximum \| Other Assets
Derivatives, Fair Value [Line Items]
Derivative Effective Date	2017-11
Derivative Maturity Date	2022-12
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	$ 8		17
Fund Portfolio \| Fund IV \| Interest Rate Cap \| Minimum \| Other Assets
Derivatives, Fair Value [Line Items]
Derivative Effective Date	2016-07
Derivative Maturity Date	2019-08
Strike Rate	3.00%
Fund Portfolio \| Fund IV \| Interest Rate Cap \| Maximum \| Other Assets
Derivatives, Fair Value [Line Items]
Derivative Effective Date	2016-11
Derivative Maturity Date	2019-12
Strike Rate	3.00%
Fund Portfolio \| Fund V
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 86,570
Fair value, derivatives, net	(951)		0
Fund Portfolio \| Fund V \| Interest Rate Swaps \| Other Liabilities
Derivatives, Fair Value [Line Items]
Fair value, liability derivatives	(972)		0
Fund Portfolio \| Fund V \| Interest Rate Swaps \| Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 16,900
Derivative Effective Date	2018-01
Derivative Maturity Date	2021-02
Fair value, asset derivatives	$ 21		$ 0
Fund Portfolio \| Fund V \| Interest Rate Swaps \| Minimum \| Other Assets
Derivatives, Fair Value [Line Items]
Strike Rate	2.41%
Fund Portfolio \| Fund V \| Interest Rate Swaps \| Maximum \| Other Assets
Derivatives, Fair Value [Line Items]
Strike Rate	2.41%

Financial Instruments and Fair Value Measurements - Schedule of Derivative Financial Instruments (Parenthetical) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)	Jul. 31, 2018 USD ($) derivative	Dec. 31, 2017 USD ($)
Derivatives, Fair Value [Line Items]
Fair value, liability derivatives	$ (7,304)		$ (1,467)
Derivative Effective Date	2018-06
Interest Rate Swaps
Derivatives, Fair Value [Line Items]
Number of derivative instruments held \| derivative		2
Fair value, liability derivatives		$ (2,900)
Derivative Effective Date	2020-07

Financial Instruments and Fair Value Measurements - Financial statements of Income (Losses) Recognized Related to Cash Flow Hedges (Details) - Cash Flow Hedging - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (loss) income recognized in other comprehensive income	$ (2,659)	$ 634	$ (646)
Amount of loss subsequently reclassified to earnings	$ 71	$ 3,317	$ 4,576

Financial Instruments and Fair Value Measurements - Schedule of Other Financial Instruments Carrying Values and Fair values (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes Receivable	$ 109,613	$ 153,829	$ 276,163	$ 147,188
Mortgage and Other Notes Payable	1,550,545	1,424,409
Unsecured notes payable and Unsecured line of credit	533,257	473,735
Level 3 \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes Receivable	109,613	153,829
Mortgage and Other Notes Payable	1,026,708	921,261
Investment in non-traded equity securities	0	0
Level 3 \| Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes Receivable	107,370	151,712
Mortgage and Other Notes Payable	1,021,075	921,891
Investment in non-traded equity securities	23,208	22,824
Level 2 \| Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unsecured notes payable and Unsecured line of credit	533,625	517,125
Level 2 \| Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unsecured notes payable and Unsecured line of credit	$ 533,954	$ 515,330

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Common Shares and Units - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	May 10, 2017	May 09, 2017
Class of Stock [Line Items]
Common shares, authorized (in shares)	200,000,000	200,000,000	200,000,000	100,000,000
Restricted shares
Class of Stock [Line Items]
Restricted stock, shares canceled for tax withholding for share based compensation (in shares)	3,288	4,314
LTIP Units and Restricted Stock
Class of Stock [Line Items]
Unit based compensation	$ 8.4	$ 8.4

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Share Repurchases - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Stockholders Equity Including Portion Attributable To Noncontrolling Interest [Abstract]
Authorized amount	$ 200,000,000
Number of shares repurchased during period (in shares)	2,294,235	0
Shares repurchased during period	$ 55,111,000
Stock repurchase fees	100,000
Remaining authorized repurchase amount	$ 144,900,000

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Dividends and Distributions - Additional Information (Details) - $ / shares						3 Months Ended								12 Months Ended
	Nov. 13, 2018	Aug. 07, 2018	May 11, 2018	Feb. 27, 2018	Nov. 08, 2017	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Class of Stock [Line Items]
Cash dividends declared per common share (in dollars per share)						$ 0.28	$ 0.27	$ 0.27	$ 0.27	$ 0.27	$ 0.26	$ 0.26	$ 0.26	$ 1.09	$ 1.05	$ 1.16
Regular Quarterly Cash Dividend
Class of Stock [Line Items]
Cash dividends declared, period increase (in dollars per share)	$ 0.01				$ 0.01
Cash dividends declared per common share (in dollars per share)	$ 0.28	$ 0.27	$ 0.27	$ 0.27	$ 0.27
Fourth Quarter Two Thousand Eighteen
Class of Stock [Line Items]
Cash dividends, declared date														Nov. 13, 2018
Cash dividends, record date														Dec. 31, 2018
Cash dividends, paid date														Jan. 15, 2019
Third Quarter Two Thousand Eighteen
Class of Stock [Line Items]
Cash dividends, declared date														Aug. 07, 2018
Cash dividends, record date														Sep. 28, 2018
Cash dividends, paid date														Oct. 15, 2018
Second Quarter Two Thousand Eighteen
Class of Stock [Line Items]
Cash dividends, declared date														May 11, 2018
Cash dividends, record date														Jun. 29, 2018
Cash dividends, paid date														Jul. 13, 2018
First Quarter Two Thousand Eighteen
Class of Stock [Line Items]
Cash dividends, declared date														Feb. 27, 2018
Cash dividends, record date														Mar. 30, 2018
Cash dividends, paid date														Apr. 13, 2018
Fourth Quarter Two Thousand Seventeen
Class of Stock [Line Items]
Cash dividends, declared date														Nov. 08, 2017
Cash dividends, record date														Dec. 29, 2017
Cash dividends, paid date														Jan. 13, 2018

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Summary of Activity in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	$ 2,215,639	$ 2,178,125	$ 1,521,354
Other comprehensive (loss) income before reclassifications	(2,659)	634	(646)
Reclassification of realized interest on swap agreements	71	3,317	4,576
Net current period other comprehensive (loss) income	(2,588)	3,951	3,930
Ending Balance	2,081,947	2,215,639	2,178,125
AOCI Attributable to Parent
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	2,614	(798)	(4,463)
Ending Balance	516	2,614	(798)
AOCI Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Net current period other comprehensive (loss) income	$ 490	$ (539)	$ (265)

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Summary of Change in Noncontrolling Interest (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance				$ 648,440					$ 648,440
Net income (loss)	$ (6,671)	$ (2,597)	$ (2,270)	(4,160)	$ 24,944	$ 13,285	$ 6,108	$ 19,971	(15,698)	$ 64,308	$ 134,592
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership									0	0	0
Issuance of Common and Preferred OP Units to acquire real estate											31,429
Acquisition of noncontrolling interest											(18,379)
Other comprehensive loss - unrealized loss on valuation of swap agreements									(2,659)	634	(646)
Change in control of previously unconsolidated investment											(75,713)
Reclassification of realized interest on swap agreements									71	3,317	4,576
Noncontrolling interest contributions									47,560	85,206	295,108
Noncontrolling interest distributions									(24,793)	(32,805)	(80,769)
Employee Long-term Incentive Plan Unit Awards									12,948	11,155	13,694
Rebalancing adjustment									0	0	0
Ending Balance	622,442				648,440				622,442	648,440
Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance				648,440				589,548	648,440	589,548	420,866
Distributions declared of $1.09,1.05 and $1.16 per Common OP Unit for year ended 2018,2017 and 2016, respectively									(6,888)	(6,453)	(6,753)
Net income (loss)									(47,137)	2,838	61,816
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership									(2,068)	(1,541)	(7,892)
Issuance of Common and Preferred OP Units to acquire real estate											31,429
Acquisition of noncontrolling interest											(25,925)
Other comprehensive loss - unrealized loss on valuation of swap agreements									(810)	(147)	(332)
Change in control of previously unconsolidated investment											(75,713)
Reclassification of realized interest on swap agreements									320	686	597
Noncontrolling interest contributions									47,560	85,206	295,108
Noncontrolling interest distributions									(24,793)	(32,805)	(80,769)
Employee Long-term Incentive Plan Unit Awards									12,374	10,457	12,768
Rebalancing adjustment									(4,556)	651	(35,652)
Ending Balance	622,442				648,440				622,442	648,440	589,548
Noncontrolling Interests \| Restatement Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ending Balance	(4,556)								(4,556)
Noncontrolling Interests \| Noncontrolling Interests in Partially-Owned Affiliates
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance				545,519				494,126	545,519	494,126	324,526
Distributions declared of $1.09,1.05 and $1.16 per Common OP Unit for year ended 2018,2017 and 2016, respectively									0	0	0
Net income (loss)									(49,709)	(1,321)	56,814
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership									0	0	0
Issuance of Common and Preferred OP Units to acquire real estate											0
Acquisition of noncontrolling interest											(25,925)
Other comprehensive loss - unrealized loss on valuation of swap agreements									(681)	(232)	(289)
Change in control of previously unconsolidated investment											(75,713)
Reclassification of realized interest on swap agreements									323	545	374
Noncontrolling interest contributions									47,560	85,206	295,108
Noncontrolling interest distributions									(24,793)	(32,805)	(80,769)
Employee Long-term Incentive Plan Unit Awards									0	0	0
Rebalancing adjustment											0
Ending Balance	518,219				545,519				518,219	545,519	494,126
Noncontrolling Interests \| Noncontrolling Interests in Partially-Owned Affiliates \| Restatement Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ending Balance	0								0
Noncontrolling Interests \| Operating Partnership, as General Partner or Managing Member
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance				$ 102,921				$ 95,422	102,921	95,422	96,340
Distributions declared of $1.09,1.05 and $1.16 per Common OP Unit for year ended 2018,2017 and 2016, respectively									(6,888)	(6,453)	(6,753)
Net income (loss)									2,572	4,159	5,002
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership									(2,068)	(1,541)	(7,892)
Issuance of Common and Preferred OP Units to acquire real estate											31,429
Acquisition of noncontrolling interest											0
Other comprehensive loss - unrealized loss on valuation of swap agreements									(129)	85	(43)
Change in control of previously unconsolidated investment											0
Reclassification of realized interest on swap agreements									(3)	141	223
Noncontrolling interest contributions									0	0	0
Noncontrolling interest distributions									0	0	0
Employee Long-term Incentive Plan Unit Awards									12,374	10,457	12,768
Rebalancing adjustment									(4,556)	651	(35,652)
Ending Balance	104,223				$ 102,921				104,223	$ 102,921	$ 95,422
Noncontrolling Interests \| Operating Partnership, as General Partner or Managing Member \| Restatement Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ending Balance	$ (4,556)								$ (4,556)

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Summary of Change in Noncontrolling Interest (Parenthetical) (Details) - $ / shares	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Minority Interest [Line Items]
Cash dividends declared per common share (in dollars per share)	$ 0.28	$ 0.27	$ 0.27	$ 0.27	$ 0.27	$ 0.26	$ 0.26	$ 0.26	$ 1.09	$ 1.05	$ 1.16
Conversion of Common OP Units to Common Shares by limited partners of the Operating Partnership (in shares)	117,978				81,453				117,978	81,453	351,250
Preferred shares converted to common stock (in shares)					5,000					5,000
Operating Partnership, as General Partner or Managing Member
Minority Interest [Line Items]
Series A Preferred OP Units (in shares)	3,329,640				3,328,873				3,329,640	3,328,873	3,308,875
Operating Partnership, as General Partner or Managing Member \| Series A Preferred Stock
Minority Interest [Line Items]
Series A Preferred OP Units (in shares)	188				188				188	188	188
Operating Partnership, as General Partner or Managing Member \| Series C Preferred Stock
Minority Interest [Line Items]
Series A Preferred OP Units (in shares)	136,593				136,593				136,593	136,593	136,593
LTIP Units
Minority Interest [Line Items]
LTIP units outstanding (in shares)	2,569,044				2,274,147				2,569,044	2,274,147	1,997,099

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Preferred OP Units - Additional Information (Details) - USD ($)	12 Months Ended			36 Months Ended	240 Months Ended
	Dec. 31, 2018	Dec. 31, 2016	Dec. 31, 1999	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Class of Stock [Line Items]
Denominator for Series A Preferred OP Unit conversion	$ 7,500			$ 7,500	$ 7,500
Common Shares
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)		12,961,000
Gotham Plaza \| Common Shares
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)		442,478
Preferred quarterly distribution per share price		$ 0.9375
Number of convertible units if share price below $28.80 (in shares)		3.4722
Number of convertible units if share price above $35.20 (in shares)		2.8409
Operating Partnership, as General Partner or Managing Member
Class of Stock [Line Items]
Series A Preferred OP Units (in shares)	3,329,640	3,308,875		3,329,640	3,329,640	3,328,873
Preferred OP Units
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)	0
Preferred OP Units \| Gotham Plaza
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)		141,593
Share price (in dollars per share)		$ 100.00
Preferred OP Units \| Gotham Plaza \| Minimum
Class of Stock [Line Items]
Share price at conversion date		28.80
Preferred OP Units \| Gotham Plaza \| Maximum
Class of Stock [Line Items]
Share price at conversion date		$ 35.20
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	$ 1,000			$ 1,000	$ 1,000
Per unit conversion amount, Series A Preferred OP Units (in dollars per unit)	$ 22.50			$ 22.50	$ 22.50
Per unit conversion annual rate, Preferred OP Units	9.00%			9.00%	9.00%
Number of preferred OP Units converted (in shares)					1,392
Units converted from Preferred OP Units (in shares)					185,600
Series A Preferred Stock \| Operating Partnership, as General Partner or Managing Member
Class of Stock [Line Items]
Series A Preferred OP Units (in shares)	188	188		188	188	188
Series C Preferred Stock \| Gotham Plaza
Class of Stock [Line Items]
Number of preferred OP Units converted (in shares)				5,000
Units converted from Preferred OP Units (in shares)				17,165
Series C Preferred Stock \| Operating Partnership, as General Partner or Managing Member
Class of Stock [Line Items]
Series A Preferred OP Units (in shares)	136,593	136,593		136,593	136,593	136,593

Leases - Operating Leases - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($) shopping_center	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Operating Leased Assets [Line Items]
Number of shopping centers with land leases \| shopping_center	6
Ground lease expense	$ 1.7	$ 1.4	$ 1.2
Rent expense capitalized	0.0	0.1	0.6
Rent expense	$ 1.0	$ 1.0	$ 1.0
Minimum
Operating Leased Assets [Line Items]
Operating lease term	1 month
Maximum
Operating Leased Assets [Line Items]
Operating lease term	60 years
Period of lease term	22 years

Leases - Schedule of Future Minimum Rental Revenues and Payments for Operating and Capital Leases (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Minimum Rental Revenues
2019	$ 187,158
2020	178,691
2021	159,749
2022	139,294
2023	121,456
Thereafter	513,853
Total	1,300,201
Minimum Rental Payments
2019	4,775
2020	4,571
2021	4,354
2022	4,404
2023	4,425
Thereafter	180,618
Total	$ 203,147

Segment Reporting - Summary of Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenues	$ 69,445	$ 66,075	$ 63,569	$ 63,124	$ 66,081	$ 62,678	$ 59,504	$ 61,999	$ 262,213	$ 250,262	$ 189,939
Depreciation and amortization									(117,549)	(104,934)	(70,011)
Property operating expenses, other operating and real estate taxes									(82,780)	(79,798)	(57,391)
General and administrative expenses									(34,343)	(33,756)	(40,648)
Impairment charge					(10,600)	(3,800)			0	(14,455)	0
Operating income									27,541	17,319	21,889
Gain on disposition of properties									5,140	48,886	81,965
Interest income									13,231	29,143	25,829
Equity in earnings of unconsolidated affiliates inclusive of gain on disposition of properties of $0, $15,336 and $35,950, respectively									9,302	23,371	39,449
Interest expense									(69,978)	(58,978)	(34,645)
Gain on change in control									0	5,571	0
Income tax provision									(934)	(1,004)	105
Net (loss) income	(6,671)	(2,597)	(2,270)	(4,160)	24,944	13,285	6,108	19,971	(15,698)	64,308	134,592
Net (income) loss attributable to noncontrolling interests	(13,801)	(11,822)	(9,935)	(11,579)	4,032	418	(5,952)	4,340	47,137	(2,838)	(61,816)
Net income attributable to Acadia	7,130	$ 9,225	$ 7,665	$ 7,419	20,912	$ 12,867	$ 12,060	$ 15,631	31,439	61,470	72,776
Real estate at cost	3,697,805				3,466,482				3,697,805	3,466,482	3,382,000
Total assets	3,958,780				3,960,247				3,958,780	3,960,247	3,995,960
Cash paid for acquisition of real estate									147,985	200,429	495,644
Cash paid for development and property improvement costs									94,834	108,142	149,434
Operating Segments \| Core Portfolio
Segment Reporting Information [Line Items]
Revenues									167,894	169,975	150,211
Depreciation and amortization									(60,903)	(61,705)	(54,582)
Property operating expenses, other operating and real estate taxes									(45,138)	(45,349)	(39,598)
General and administrative expenses									0	0
Impairment charge										0
Operating income									61,853	62,921	56,031
Gain on disposition of properties									0	0
Interest income									0	0
Equity in earnings of unconsolidated affiliates inclusive of gain on disposition of properties of $0, $15,336 and $35,950, respectively									7,415	3,735	3,774
Interest expense									(27,575)	(28,618)	(27,435)
Gain on change in control										5,571
Income tax provision									0	0
Net (loss) income									41,693	43,609	32,370
Net (income) loss attributable to noncontrolling interests									752	(1,107)	(3,411)
Net income attributable to Acadia									42,445	42,502	28,959
Real estate at cost	2,069,439				2,032,485				2,069,439	2,032,485	1,982,763
Total assets	2,232,695				2,305,663				2,232,695	2,305,663	2,271,620
Cash paid for acquisition of real estate									1,343	0	323,880
Cash paid for development and property improvement costs									32,662	42,026	13,434
Operating Segments \| Funds
Segment Reporting Information [Line Items]
Revenues									94,319	80,287	39,728
Depreciation and amortization									(56,646)	(43,229)	(15,429)
Property operating expenses, other operating and real estate taxes									(37,642)	(34,449)	(17,793)
General and administrative expenses									0	0
Impairment charge										(14,455)
Operating income									31	(11,846)	6,506
Gain on disposition of properties									5,140	48,886	81,965
Interest income									0	0
Equity in earnings of unconsolidated affiliates inclusive of gain on disposition of properties of $0, $15,336 and $35,950, respectively									1,887	19,636	35,675
Interest expense									(42,403)	(30,360)	(7,210)
Gain on change in control										0
Income tax provision									0	0
Net (loss) income									(35,345)	26,316	116,936
Net (income) loss attributable to noncontrolling interests									46,385	(1,731)	(58,405)
Net income attributable to Acadia									11,040	24,585	58,531
Real estate at cost	1,628,366				1,433,997				1,628,366	1,433,997	1,399,237
Total assets	1,616,472				1,500,755				1,616,472	1,500,755	1,448,177
Cash paid for acquisition of real estate									146,642	200,429	171,764
Cash paid for development and property improvement costs									62,172	66,116	136,000
Operating Segments \| Structured Financing
Segment Reporting Information [Line Items]
Revenues									0	0
Depreciation and amortization									0	0
Property operating expenses, other operating and real estate taxes									0	0
General and administrative expenses									0	0
Impairment charge										0
Operating income									0	0
Gain on disposition of properties									0	0
Interest income									13,231	29,143	25,829
Equity in earnings of unconsolidated affiliates inclusive of gain on disposition of properties of $0, $15,336 and $35,950, respectively									0	0
Interest expense									0	0
Gain on change in control										0
Income tax provision									0	0
Net (loss) income									13,231	29,143	25,829
Net (income) loss attributable to noncontrolling interests									0	0
Net income attributable to Acadia									13,231	29,143	25,829
Real estate at cost	0				0				0	0
Total assets	109,613				153,829				109,613	153,829	276,163
Cash paid for acquisition of real estate									0	0
Cash paid for development and property improvement costs									0	0
Unallocated
Segment Reporting Information [Line Items]
Revenues									0	0
Depreciation and amortization									0	0
Property operating expenses, other operating and real estate taxes									0	0
General and administrative expenses									(34,343)	(33,756)	(40,648)
Impairment charge										0
Operating income									(34,343)	(33,756)	(40,648)
Gain on disposition of properties									0	0
Interest income									0	0
Equity in earnings of unconsolidated affiliates inclusive of gain on disposition of properties of $0, $15,336 and $35,950, respectively									0	0
Interest expense									0	0
Gain on change in control										0
Income tax provision									(934)	(1,004)	105
Net (loss) income									(35,277)	(34,760)	(40,543)
Net (income) loss attributable to noncontrolling interests									0	0
Net income attributable to Acadia									(35,277)	(34,760)	$ (40,543)
Real estate at cost	0				0				0	0
Total assets	$ 0				$ 0				0	0
Cash paid for acquisition of real estate									0	0
Cash paid for development and property improvement costs									$ 0	$ 0

Segment Reporting - Summary of Segment Information (Parenthetical) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Nov. 16, 2017
Segment Reporting Information [Line Items]
Equity in earnings of unconsolidated affiliates inclusive of gain on disposition of properties of $0, $15,336 and $35,950, respectively	$ 9,302	$ 23,371	$ 39,449
Core Portfolio
Segment Reporting Information [Line Items]
Equity method investment, ownership percentage	75.22%	61.11%		22.22%
Core Portfolio \| Town Center
Segment Reporting Information [Line Items]
Equity method investment, ownership percentage	75.22%
Operating Segments \| Core Portfolio
Segment Reporting Information [Line Items]
Equity in earnings of unconsolidated affiliates inclusive of gain on disposition of properties of $0, $15,336 and $35,950, respectively	$ 7,415	$ 3,735	3,774
Operating Segments \| Core Portfolio \| Town Center
Segment Reporting Information [Line Items]
Equity in earnings of unconsolidated affiliates inclusive of gain on disposition of properties of $0, $15,336 and $35,950, respectively	$ 5,800	$ 1,900	$ 900
Equity method investment, ownership percentage	75.22%			22.22%
Property related cost	$ 700

- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ References + Details

Share Incentive and Other Compensation - Additional Information (Details) - USD ($)	3 Months Ended	9 Months Ended		12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit based compensation				$ 12,948,000	$ 11,155,000	$ 13,695,000
Trustee fees		$ 1,300,000	$ 1,300,000
Total unrecognized compensation cost related to nonvested awards		$ 14,100,000
Weighted-average period over which cost is expected to be recognized		1 year 7 months 6 days
Performance Period Ending December 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage				33.30%
Award vesting period				3 years
LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures	26,632
Compensation expense	$ 600,000
Compensation expense related to acceleration of previously granted	$ 1,700,000
Total fair value of shares that vested		$ 12,800,000			7,300,000
LTIP Units \| Trustee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures		17,427
Shares granted to trustees for trustee fees vesting on one year anniversary of grant date		8,949
LTIP Units \| Performance Period Ending December 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage				66.70%
Award vesting period				3 years
LTIP Units \| Tranche One \| Trustee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures		8,478
Restricted shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of shares that vested		$ 800,000			$ 700,000
Restricted shares \| Trustee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures		17,050
Shares granted to trustees for trustee fees vesting on one year anniversary of grant date		5,181
Restricted shares \| Tranche One \| Trustee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures		11,869
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				$ 10,400,000
Weighted average grant date fair value, grants (in dollars per share)		$ 26.64			$ 31.69
LTIP Units and Restricted Stock \| Trustee
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%
LTIP Units and Restricted Stock \| General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit based compensation				$ 8,400,000	$ 8,400,000
LTIP Units and Restricted Stock \| Performance Period Ending December 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				3 years
LTIP Units and Restricted Stock \| Performance Fails To Achieve, Earned Performance-Based Shares Vest At End Of Performance Period
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage				60.00%
LTIP Units and Restricted Stock \| Performance Fails To Achieve
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage				40.00%
Award vesting period				2 years
LTIP Units and Restricted Stock \| Minimum \| TSR percentile falls between the 25th percentile and the 50th percentile
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage				50.00%
LTIP Units and Restricted Stock \| Minimum \| TSR percentile falls between the 50th percentile and 75th percentile
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage				100.00%
LTIP Units and Restricted Stock \| Maximum \| TSR percentile falls between the 25th percentile and the 50th percentile
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage				100.00%
LTIP Units and Restricted Stock \| Maximum \| TSR percentile falls between the 50th percentile and 75th percentile
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage				200.00%
Employee Benefit Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense				$ 300,000	$ 200,000	$ 200,000
Share Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	1,176,340			1,176,340
Share Incentive Plan \| LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures				381,821
Share Incentive Plan \| Restricted shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures				5,767
Performance Shares 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period				3 years
Volatility rate				(18.00%)
Risk-free interest rates				(2.40%)
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%
Long Term Investment Alignment Program \| Fund III
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		$ 0	$ 600,000
Percentage of promote awarded as share based compensation award							25.00%
Long Term Investment Alignment Program \| Fund IV
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of promote awarded as share based compensation award							22.80%
Awards in connection with fund to have intrinsic value		$ 0

Share Incentive and Other Compensation - Schedule of Unvested Shares and LTIP Units (Details) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Restricted shares
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)	41,327	46,499	49,899
Shares granted (in shares)	22,817	19,442	21,675
Shares vested (in shares)	(25,261)	(23,430)	(24,886)
Shares forfeited (in shares)	(428)	(1,184)	(189)
Shares unvested, End of period (in shares)	38,455	41,327	46,499
Weighted Grant-Date Fair Value
Shares unvested, Weighted average grant date fair value, Beginning of period (in dollars per share)	$ 26.92	$ 27.58	$ 25.90
Shares granted, Weighted average grant date fair value (in dollars per share)	23.65	29.85	33.35
Shares vested, Weighted average grant date fair value (in dollars per share)	30.79	30.47	29.17
Shares forfeited, Weighted average grant date fair value (in dollars per share)	27.25	32.65	35.37
Shares unvested, Weighted average grant date fair value, End of period (in dollars per share)	$ 22.44	$ 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)	910,099	856,877	1,020,121
Shares granted (in shares)	425,880	310,551	359,484
Shares vested (in shares)	(431,827)	(257,124)	(522,680)
Shares forfeited (in shares)	(12,266)	(205)	(48)
Shares unvested, End of period (in shares)	891,886	910,099	856,877
Weighted Grant-Date Fair Value
Shares unvested, Weighted average grant date fair value, Beginning of period (in dollars per share)	$ 28.28	$ 26.99	$ 23.92
Shares granted, Weighted average grant date fair value (in dollars per share)	26.80	31.80	34.40
Shares vested, Weighted average grant date fair value (in dollars per share)	29.72	28.27	26.08
Shares forfeited, Weighted average grant date fair value (in dollars per share)	28.57	32.49	35.37
Shares unvested, Weighted average grant date fair value, End of period (in dollars per share)	$ 26.87	$ 28.28	$ 26.99

Share Incentive and Other Compensation - Employee Share Purchase Plan and Deferred Share Plan - Additional Information (Details) - USD ($)	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee share purchase discount rate	15.00%
Employee share purchase maximum purchase amount	$ 25,000
Common Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee share purchase (in shares)	3,495	4,514

Federal Income Taxes - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Minimum distribution percentage of annual taxable income to qualify as REIT	90.00%
Maximum percentage of total assets consisting of securities of taxable REIT subsidiaries	20.00%
Deferred tax assets, additional tax basis in RCP Investments	$ 0.0	$ 1.0
Deferred tax assets, capital loss carryforwards	0.1	0.0
Deferred tax assets, operating loss carryforwards	$ 2.0	$ 1.1

Federal Income Taxes - Reconciliation of Net Income to Taxable Income (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Net income attributable to Acadia	$ 7,130	$ 9,225	$ 7,665	$ 7,419	$ 20,912	$ 12,867	$ 12,060	$ 15,631	$ 31,439	$ 61,470	$ 72,776
Deferred cancellation of indebtedness income									2,050	2,050	2,050
Deferred rental and other income									1,222	(934)	1,610
Book/tax difference - depreciation and amortization									23,166	21,334	15,189
Straight-line rent and above- and below-market rent adjustments									(12,129)	(10,559)	(7,882)
Book/tax differences - equity-based compensation									6,042	5,325	10,307
Joint venture equity in earnings, net									13,905	9,114	(2,011)
Impairment charges and reserves									0	0	769
Acquisition costs									326	1,135	5,116
Gains									0	(5,181)	0
Book/tax differences - miscellaneous									(2,821)	930	(4,924)
Taxable income									63,200	84,684	93,000
Distributions declared									$ 89,122	$ 87,848	$ 91,053

Federal Income Taxes - Tax Status of Dividends (Details) - $ / shares	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Contingency [Line Items]
Total (in dollars per share)	$ 0.28	$ 0.27	$ 0.27	$ 0.27	$ 0.27	$ 0.26	$ 0.26	$ 0.26	$ 1.09	$ 1.05	$ 1.16
Characterization Of Distributions For Federal Income Tax Purposes
Income Tax Contingency [Line Items]
Qualified dividend (in dollars per share)									0	0	0
Capital gain (in dollars per share)									0	0.23	0.39
Total (in dollars per share)									$ 0.87	$ 1.05	$ 1.16
Qualified dividend									0.00%	0.00%	0.00%
Capital gain									0.00%	22.00%	34.00%
Total									100.00%	100.00%	100.00%
Characterization Of Distributions For Federal Income Tax Purposes \| Non-Section 199A
Income Tax Contingency [Line Items]
Ordinary income (in dollars per share)									$ 0	$ 0.82	$ 0.77
Ordinary income									0.00%	78.00%	66.00%
Characterization Of Distributions For Federal Income Tax Purposes \| Section 199A
Income Tax Contingency [Line Items]
Ordinary income (in dollars per share)									$ 0.87	$ 0	$ 0
Ordinary income									100.00%	0.00%	0.00%

Federal Income Taxes - Income and Provision for Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
(Provision) benefit for income taxes:
TRS net loss before noncontrolling interests									$ 31,439	$ 61,470	$ 72,776
Net loss (income) attributable to noncontrolling interests	$ (13,801)	$ (11,822)	$ (9,935)	$ (11,579)	$ 4,032	$ 418	$ (5,952)	$ 4,340	47,137	(2,838)	(61,816)
Net (loss) income	$ (6,671)	$ (2,597)	$ (2,270)	$ (4,160)	$ 24,944	$ 13,285	$ 6,108	$ 19,971	(15,698)	64,308	134,592
TRS [Member]
Income Tax Contingency [Line Items]
TRS loss before income taxes									(2,609)	(3,604)	(1,583)
(Provision) benefit for income taxes:
Federal									(377)	(982)	378
State and local									26	423	97
TRS net loss before noncontrolling interests									(2,960)	(4,163)	(1,108)
Net loss (income) attributable to noncontrolling interests									4	8	(9)
Net (loss) income									$ (2,956)	$ (4,155)	$ (1,117)

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

+ Details

Federal Income Taxes - Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Federal tax benefit at statutory tax rate	$ (548)	$ (1,225)	$ (538)
TRS state and local taxes, net of Federal benefit	(165)	(190)	(84)
Permanent differences, net	951	1,131	1,663
Prior year over-accrual, net	0	(1,541)	0
Effect of Tax Cuts and Jobs Act	0	1,982	0
Other	172	404	(1,516)
REIT state and local income and franchise taxes	524	443	370
Total provision (benefit) for income taxes	$ 934	$ 1,004	$ (105)

Earnings Per Common Share - Additional Information (Details)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Description of conversion of common OP units to common shares	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.
Conversion of common OP units to common shares	100.00%

Earnings Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Numerator:
Net income attributable to Acadia									$ 31,439	$ 61,470	$ 72,776
Less: net income attributable to participating securities									(267)	(642)	(793)
Income from continuing operations net of income attributable to participating securities									$ 31,172	$ 60,828	$ 71,983
Denominator:
Weighted average shares for basic earnings per share (in shares)									82,080,159	83,682,789	76,231,000
Effect of dilutive securities:
Employee unvested restricted shares (in shares)									0	2,682	12,550
Denominator for diluted earnings per share (in shares)	81,591	81,566	81,756	83,438	83,733	83,700	83,662	83,646	82,080,159	83,685,471	76,243,550
Basic and diluted earnings per share (in dollars per share)									$ 0.38	$ 0.73	$ 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	136,593	141,593
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)									474,278	479,978	410,207
Restricted shares
Anti-Dilutive Shares Excluded from Denominator:
Antidilutive securities excluded from computation of earnings per share (in shares)									36,879	41,299	50,156

Summary of Quarterly Financial Information (Unaudited) (Details) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018 USD ($) property $ / shares shares	Sep. 30, 2018 USD ($) property $ / shares shares	Jun. 30, 2018 USD ($) $ / shares shares	Mar. 31, 2018 USD ($) $ / shares shares	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, 2018 USD ($) property $ / shares shares	Dec. 31, 2017 USD ($) property $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares
Interim Period, Costs Not Allocable [Line Items]
Revenues	$ 69,445	$ 66,075	$ 63,569	$ 63,124	$ 66,081	$ 62,678	$ 59,504	$ 61,999	$ 262,213	$ 250,262	$ 189,939
Net (loss) income	(6,671)	(2,597)	(2,270)	(4,160)	24,944	13,285	6,108	19,971	(15,698)	64,308	134,592
Net loss attributable to noncontrolling interests	13,801	11,822	9,935	11,579	(4,032)	(418)	5,952	(4,340)	(47,137)	2,838	61,816
Net income attributable to Acadia	$ 7,130	$ 9,225	$ 7,665	$ 7,419	$ 20,912	$ 12,867	$ 12,060	$ 15,631	$ 31,439	$ 61,470	$ 72,776
Basic (in dollars per share) \| $ / shares	$ 0.09	$ 0.11	$ 0.09	$ 0.09	$ 0.25	$ 0.15	$ 0.14	$ 0.18
Diluted (in dollars per share) \| $ / shares	$ 0.09	$ 0.11	$ 0.09	$ 0.09	$ 0.25	$ 0.15	$ 0.14	$ 0.18
Weighted average number of shares: Basic \| shares	81,591	81,566	81,756	83,434	83,733	83,700	83,662	83,635
Weighted average number of shares: Diluted \| shares	81,591	81,566	81,756	83,438	83,733	83,700	83,662	83,646	82,080,159	83,685,471	76,243,550
Dividend per common share \| $ / shares	$ 0.28	$ 0.27	$ 0.27	$ 0.27	$ 0.27	$ 0.26	$ 0.26	$ 0.26	$ 1.09	$ 1.05	$ 1.16
Number of retail properties \| property	171								171
Impairment charges					$ 10,600	$ 3,800			$ 0	$ 14,455	$ 0
Gain on change in control and other					5,600
Noncontrolling Interests
Interim Period, Costs Not Allocable [Line Items]
Net (loss) income									$ (47,137)	$ 2,838	$ 61,816
Impairment charges					7,600	2,700
Disposed of by sale
Interim Period, Costs Not Allocable [Line Items]
Gain (loss) on disposal		$ 5,100			$ 35,900	$ 13,000	$ 3,300	$ 14,500
Number of retail properties \| property		2			3	2		2		3
Disposed of by sale \| Partnership Interest
Interim Period, Costs Not Allocable [Line Items]
Gain (loss) on disposal							$ 800	$ 2,700
Disposed of by sale \| Noncontrolling Interests
Interim Period, Costs Not Allocable [Line Items]
Gain (loss) on disposal		$ 3,900			$ 26,700	$ 10,700

Subsequent Events - Additional Information (Details) - USD ($)				12 Months Ended
	Jan. 23, 2019	Jan. 09, 2019	Jan. 04, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 11, 2019
Subsequent Event [Line Items]
Derivative, notional amount				$ 69,670,000
Proceeds from the disposition of properties				63,866,000	$ 260,711,000	$ 150,378,000
Fund III
Subsequent Event [Line Items]
Capital called				423,900,000
Capital called company share amount				551,900,000
Interest Rate Swaps
Subsequent Event [Line Items]
Derivative, notional amount				$ 50,000,000
Derivative fixed interest rate				2.80%
Interest Rate Swaps \| Mortgages
Subsequent Event [Line Items]
Derivative, notional amount				$ 136,600,000
Derivative fixed interest rate				2.86%
Subsequent Event
Subsequent Event [Line Items]
Derivative remaining maturity periods			10 years
Subsequent Event \| Fund III \| 3104 M Street Property
Subsequent Event [Line Items]
Proceeds from the disposition of properties	$ 10,500,000
Subsequent Event \| Renaissance Portfolio \| Fund III \| 3104 M Street Property
Subsequent Event [Line Items]
Equity method investment, ownership percentage	20.00%
Subsequent Event \| Renaissance Portfolio \| Fund III \| 3104 M Street Property \| Mortgages
Subsequent Event [Line Items]
Equity method investments	$ 4,700,000
Subsequent Event \| Interest Rate Swaps
Subsequent Event [Line Items]
Derivative, notional amount			$ 100,000,000
Derivative fixed interest rate			2.60%
Subsequent Event \| Interest Rate Swaps \| Fund V \| Elk Grove Commons - Elk Grove, CA
Subsequent Event [Line Items]
Borrowings, amount							$ 41,500,000
Subsequent Event \| Fund V
Subsequent Event [Line Items]
Capital called		$ 33,200,000
Capital called company share amount		$ 6,700,000

SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for deferred tax asset
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 1,530	$ 859	$ 0
Charged to Expenses	0	0	0
Adjustments to Valuation Accounts	0	671	859
Deductions	(1,530)	0	0
Balance at End of Year	0	1,530	859
Allowance for uncollectible accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	5,920	5,720	7,451
Charged to Expenses	2,532	200	0
Adjustments to Valuation Accounts	(531)	0	0
Deductions	0	0	(1,731)
Balance at End of Year	7,921	5,920	5,720
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, 2018	Dec. 31, 2017	Dec. 31, 2016
Real Estate And Accumulated Depreciation Disclosure [Abstract]
Balance at beginning of year	$ 3,466,482	$ 3,382,000	$ 2,736,283
Other improvements	100,077	55,763	152,129
Property acquisitions	134,559	179,292	761,400
Property dispositions or held for sale assets	(34,666)	(189,895)	(134,332)
Other	(483)		(9,844)
Deconsolidation of previously consolidated investments			(123,636)
Consolidation of previously unconsolidated investments	31,836	39,322
Balance at end of year	$ 3,697,805	$ 3,466,482	$ 3,382,000

SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION - Reconciliation of Accumulated Depreciation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Real Estate And Accumulated Depreciation Disclosure [Abstract]
Balance at beginning of year	$ 339,862	$ 287,066	$ 298,703
Depreciation related to real estate	78,453	73,268	49,269
Property dispositions	(1,658)	(20,472)	(27,829)
Deconsolidation of previously consolidated investments			(33,077)
Balance at end of year	$ 416,657	$ 339,862	$ 287,066

SCHEDULE IV - MORTGAGE LOANS ON REAL ESTATE - Loans On Real Estate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Mortgage Loans on Real Estate [Line Items]
Face Amount of Notes Receivable	$ 215,200
Net carrying amount of notes receivable	$ 109,613	$ 153,829	$ 276,163	$ 147,188
First Mortgage Loan, 6.0% Loan, Due 4/30/2020
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	$ 17,802
First Mortgage Loan, 8.1% Loan, Due 4/30/2019
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	$ 38,673
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	$ 32,582
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	$ 5,306
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, 2018	Dec. 31, 2017	Dec. 31, 2016
Movement in Mortgage Loans on Real Estate [Roll Forward]
Balance at beginning of year	$ 153,829	$ 276,163	$ 147,188
Additions	3,805	11,371	171,794
Repayments	(26,000)	(32,000)	(42,819)
Conversion to real estate through receipt of deed	(22,021)	(101,705)
Balance at end of year	$ 109,613	$ 153,829	$ 276,163

Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Commitments And Contingencies Disclosure [Abstract]
Contractual obligation	$ 55.5	$ 98.7
Letters of credit, outstanding amount	$ 19.7	$ 19.7

Segment Reporting - Additional Information (Details)	12 Months Ended
Segment Reporting - Additional Information (Details)	Dec. 31, 2018 segment
Segment Reporting [Abstract]
Number of reportable segments	3

Share Incentive and Other Compensation - Employee 401 (k) Plan - Additional Information (Details)	9 Months Ended
	Sep. 30, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Employer matching contribution	50.00%
Maximum annual contribution per employee	6.00%
Maximum employee annual salary contribution	15.00%