Acadia Realty Trust (AKR) 10-Q 3 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2018	Apr. 30, 2018
Document and Entity Information [Abstract]
Entity Registrant Name	ACADIA REALTY TRUST
Entity Central Index Key	899,629
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Common Stock, Shares Outstanding		81,590,390

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
ASSETS
Operating real estate, net	$ 2,988,377	$ 2,952,918
Real estate under development	182,380	173,702
Net investments in real estate	3,170,757	3,126,620
Notes receivable, net	108,959	153,829
Investments in and advances to unconsolidated affiliates	311,540	302,070
Other assets, net	216,514	214,959
Cash and cash equivalents	39,344	74,823
Rents receivable, net	53,983	51,738
Restricted cash	12,517	10,846
Assets of properties held for sale	25,362	25,362
Total assets	3,938,976	3,960,247
LIABILITIES
Mortgage and other notes payable, net	911,527	909,174
Unsecured notes payable, net	529,756	473,735
Unsecured line of credit	14,000	41,500
Accounts payable and other liabilities	209,090	210,052
Capital lease obligation	70,732	70,611
Dividends and distributions payable	23,978	24,244
Distributions in excess of income from, and investments in, unconsolidated affiliates	15,226	15,292
Total liabilities	1,774,309	1,744,608
Commitments and contingencies
Acadia Shareholders' Equity
Common shares, $0.001 par value, authorized 200,000,000 shares, issued and outstanding 82,450,745 and 83,708,140 shares, respectively	82	84
Additional paid-in capital	1,564,067	1,596,514
Accumulated other comprehensive income	7,376	2,614
Distributions in excess of accumulated earnings	(46,856)	(32,013)
Total Acadia shareholders’ equity	1,524,669	1,567,199
Noncontrolling interests	639,998	648,440
Total equity	2,164,667	2,215,639
Total liabilities and equity	$ 3,938,976	$ 3,960,247

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Mar. 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	100,000,000
Common shares, issued (in shares)	82,450,745	83,708,140
Common shares, outstanding (in shares)	82,450,745	83,708,140

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues
Rental income	$ 50,779	$ 48,585
Expense reimbursements	11,208	12,316
Other	1,137	1,098
Total revenues	63,124	61,999
Operating expenses
Depreciation and amortization	28,576	24,536
General and administrative	8,470	8,469
Real estate taxes	8,959	10,606
Property operating	10,338	8,197
Other operating	80	294
Total operating expenses	56,423	52,102
Operating income	6,701	9,897
Equity in earnings and gains of unconsolidated affiliates inclusive of gains on disposition of properties of $0 and $11,846 respectively	1,684	12,703
Interest income	3,737	8,984
Interest expense	(15,890)	(11,488)
(Loss) income from continuing operations before income taxes	(3,768)	20,096
Income tax provision	(392)	(125)
Net (loss) income	(4,160)	19,971
Net loss (income) attributable to noncontrolling interests	11,579	(4,340)
Net income attributable to Acadia	$ 7,419	$ 15,631
Basic and diluted earnings per share (in dollars per share)	$ 0.09	$ 0.18

CONSOLIDATED STATEMENTS OF INC5

CONSOLIDATED STATEMENTS OF INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement [Abstract]
Gains (losses) on disposition of properties	$ 0	$ 11,846

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (4,160)	$ 19,971
Other comprehensive income:
Unrealized income on valuation of swap agreements	5,653	118
Reclassification of realized interest on swap agreements	363	963
Other comprehensive income	6,016	1,081
Comprehensive income	1,856	21,052
Comprehensive loss (income) attributable to noncontrolling interests	10,325	(4,185)
Comprehensive income attributable to Acadia	$ 12,181	$ 16,867

CONSOLIDATED STATEMENTS OF SHAR

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Shares	Additional Paid-in Capital	Accumulated Other Comprehensive (Loss) Income	Distributions in Excess of Accumulated Earnings	Total Common Shareholders’ Equity	Noncontrolling Interests
Beginning 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	$ 0	438			438	(438)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership (in Shares)		25,000
Dividends declared ($0.27 and $0.26 per Common Share/OP Unit for Three Months Ended March 31, 2018 and 2017)	(23,366)				(21,749)	(21,749)	(1,617)
Employee and trustee stock compensation, net	4,235		94			94	4,141
Employee and trustee stock compensation, net (in Shares)		7,000
Noncontrolling interest distributions	(3,822)						(3,822)
Noncontrolling interest contributions	20,269						20,269
Reallocation of noncontrolling interests	0		(5,693)			(5,693)	5,693
Comprehensive income	21,052			1,236	15,631	16,867	4,185
Ending Balance at Mar. 31, 2017	2,196,493	$ 84	1,589,765	438	(11,753)	1,578,534	617,959
Balance (in Shares) at Mar. 31, 2017		83,630,000
Beginning 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]
Repurchase of Common Shares (in shares)	0
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		642			642	(642)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership (in Shares)		38,000
Repurchase of Common Shares	$ (31,961)	$ (2)	(31,959)			(31,961)
Repurchase of Common Shares (in shares)	(1,304,194)	(1,304,000)
Dividends declared ($0.27 and $0.26 per Common Share/OP Unit for Three Months Ended March 31, 2018 and 2017)	$ (23,983)				(22,262)	(22,262)	(1,721)
Employee and trustee stock compensation, net	3,811		95			95	3,716
Employee and trustee stock compensation, net (in Shares)		9,000
Noncontrolling interest distributions	(695)						(695)
Reallocation of noncontrolling interests	0		(1,225)			(1,225)	1,225
Comprehensive income	1,856			4,762	7,419	12,181	(10,325)
Ending Balance at Mar. 31, 2018	$ 2,164,667	$ 82	$ 1,564,067	$ 7,376	$ (46,856)	$ 1,524,669	$ 639,998
Balance (in Shares) at Mar. 31, 2018	82,450,745	82,451,000

CONSOLIDATED STATEMENTS OF SHA8

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Stockholders' Equity [Abstract]
Cash dividends declared per common share (in dollars per share)	$ 0.27	$ 0.26

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
CASH FLOWS FROM OPERATING ACTIVITIES
Net (loss) income	$ (4,160)	$ 19,971
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	28,576	24,536
Distributions of operating income from unconsolidated affiliates	4,724	1,299
Equity in earnings and gains of unconsolidated affiliates	(1,684)	(12,703)
Stock compensation expense	3,809	4,235
Amortization of financing costs	1,375	1,169
Other, net	(1,889)	(2,908)
Changes in assets and liabilities:
Other liabilities	1,461	1,076
Prepaid expenses and other assets	(2,240)	(5,736)
Rents receivable, net	(2,359)	(6,723)
Accounts payable and accrued expenses	(4,674)	273
Net cash provided by operating activities	22,939	24,489
CASH FLOWS FROM INVESTING ACTIVITIES
Acquisition of real estate	(46,171)	(34,688)
Development and property improvement costs	(18,136)	(27,015)
Issuance of or advances on notes receivable	(2,951)	(150)
Investments in and advances to unconsolidated affiliates	(1,847)	(3,174)
Return of capital from unconsolidated affiliates and other	16,210	2,677
Proceeds from notes receivable	26,000	0
Return of deposits for properties under contract	1,750	0
Proceeds from disposition of properties of unconsolidated affiliates	0	25,080
Payment of deferred leasing costs	(1,134)	(2,033)
Net cash used in investing activities	(26,279)	(39,303)
CASH FLOWS FROM FINANCING ACTIVITIES
Principal payments on mortgage and other notes	(45,246)	(5,236)
Principal payments on unsecured debt	(420,500)	(94,100)
Proceeds received on mortgage and other notes	47,273	93,044
Proceeds from unsecured debt	447,800	20,000
Payments for repurchase of Common Shares	(31,961)	0
Capital contributions from noncontrolling interests	0	20,264
Distributions to noncontrolling interests	(2,411)	(6,163)
Dividends paid to Common Shareholders	(22,601)	(34,275)
Deferred financing and other costs	(2,822)	(1,701)
Net cash used in financing activities	(30,468)	(8,167)
Decrease in cash and restricted cash	(33,808)	(22,981)
Cash of $74,823 and $71,805, respectively and restricted cash of $10,846 and $22,904 respectively, beginning of period	85,669	94,709	$ 94,709
Cash of $39,344 and $47,707, respectively and restricted cash of $12,517 and $24,021 respectively, end of period	51,861	71,728	$ 85,669
Supplemental disclosure of cash flow information
Cash paid during the period for interest, net of capitalized interest of $1,492 and $5,009, respectively	11,910	9,629
Cash paid for income taxes, net of (refunds)	673	220
Supplemental disclosure of non-cash investing activities
Assumption of accounts payable and accrued expenses through acquisition of real estate	425	662
Acquisition of undivided interest in a property through conversion of notes receivable	$ 22,201	$ 0

CONSOLIDATED STATEMENTS OF CA10

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Cash Flows [Abstract]
Cash and cash equivalents	$ 39,344	$ 47,707
Restricted cash	12,517	24,021
Cash paid for capitalized interest	$ 1,492	$ 5,009

Organization, Basis of Presenta

Organization, Basis of Presentation and Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization, Basis of Presentation and Summary of Significant Accounting Policies	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 March 31, 2018 and December 31, 2017 , the Company controlled approximately 94% and 95% , respectively, 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 March 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 57 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 175 Core Portfolio and Fund properties primarily consist of street and urban retail, and suburban shopping centers. In addition, the Company, together with the investors in the Funds, invest in operating companies through Acadia Mervyn Investors I, LLC (“Mervyns I,” 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 March 31, 2018 Unfunded Commitment Equity Interest Held By Operating Partnership (a) Preferred Return Total Distributions as of March 31, 2018 (b) Fund II and Mervyns II 6/2004 28.33% $ 347.1 $ — 28.33% 8% $ 131.6 Fund III 5/2007 24.54% 411.5 38.5 24.54% 6% 551.9 Fund IV 5/2012 23.12% 412.7 117.3 23.12% 6% 131.5 Fund V 8/2016 20.10% 45.8 474.2 20.10% 6% — __________ (a) Amount represents the current economic ownership at March 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. Basis of Presentation Segments At March 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. Each property is considered a separate operating segment; however, each property on a stand-alone basis represents less than 10% of revenues, profit or loss, and assets of the combined reported operating segment and meets the majority of the aggregations criteria under the applicable standard. Principles of Consolidation The consolidated financial statements include the consolidated accounts of the Company and its investments in partnerships and limited liability companies in which the Company has control in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) Topic 810 “Consolidation” (“ASC Topic 810”). The ownership interests of other investors in these entities are recorded as noncontrolling interests. All significant intercompany balances and transactions have been eliminated in consolidation. Investments in entities for which the Company has the ability to exercise significant influence over, but does not have financial or operating control, are accounted for using the equity method of accounting. Accordingly, the Company’s share of the earnings (or losses) of these entities are included in consolidated net income. The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information and with the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”). Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. Operating results for the interim periods presented are not necessarily indicative of the results that may be expected for the full fiscal year. The information furnished in the accompanying consolidated financial statements reflects all adjustments that, in the opinion of management, are necessary for a fair presentation of the aforementioned consolidated financial statements for the interim periods. Such adjustments consisted of normal recurring items. These consolidated financial statements should be read in conjunction with the Company’s 2017 Annual Report on Form 10-K, as filed with the SEC on February 27, 2018. Use of Estimates GAAP requires the Company’s management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. The most significant assumptions and estimates relate to the valuation of real estate, depreciable lives, revenue recognition and the collectability of notes receivable and rents receivable. Application of these estimates and assumptions requires the exercise of judgment as to future uncertainties and, as a result, actual results could differ from these estimates. Recently Adopted Accounting Pronouncements In May 2014, the FASB issued Accounting Standards Update (“ASU”) No. 2014-09 , Revenue from Contracts with Customers. ASU 2014-09 is a comprehensive new revenue recognition model requiring a company to recognize revenue to depict the transfer of goods or services to a customer at an amount reflecting the consideration it expects to receive in exchange for those goods or services. ASU 2014-09 does not apply to the Company’s lease revenues, but will apply to reimbursed tenant costs. Additionally, this guidance modifies disclosures regarding the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. In August 2015, the FASB issued ASU 2015-14, which defers the effective date of ASU 2014-09 for all entities by one year, until years beginning in 2018, with early adoption permitted but not before 2017. Entities may adopt ASU 2014-09 using either a full retrospective approach reflecting the application of the standard in each prior reporting period with the option to elect certain practical expedients or a modified retrospective approach with the cumulative effect, recognized at the date of adoption. Substantially all of the Company’s revenue is derived from its leases and therefore falls outside of the scope of this guidance. The Company implemented the standard 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 Company’s revenue recognition. However, the recognition of gains on sales of properties may be impacted prospectively under limited circumstances under which collectability may not be reasonably assured or if the Company has continuing involvement with a sold property. In August 2016, the FASB issued ASU No. 2016-15 , Statement of Cash Flows – Classification of Certain Cash Receipts and Cash Payments. ASU 2016-15 provides guidance on certain specific cash flow issues, including, but not limited to, debt prepayment or extinguishment costs, contingent consideration payments made after a business combination and distributions received from equity method investees. ASU 2016-15 is effective for periods beginning after December 15, 2017, with early adoption permitted and shall be applied retrospectively where practicable. The Company adopted ASU 2016-15 effective January 1, 2018 and elected the “cumulative distribution approach” whereby distributions received from equity method investments would be classified as cash flows from operations to the extent of equity earnings and then as cash flows from investing activities thereafter. Upon the adoption, the Company reclassified $7.3 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 three months ended March 31, 2017 . In November 2016, the FASB issued ASU 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. ASU 2016-18 is effective for public business entities in fiscal years beginning after December 15, 2017, with early adoption permitted. The Company adopted this guidance effective January 1, 2018. Upon the adoption, the Company reclassified $1.0 million of its cash inflows from operating activities to change in cash and restricted cash in its historical presentation of cash flows for the three months ended March 31, 2017 . 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. It is expected that the new standard will reduce the number of future real estate acquisitions that will be accounted for as business combinations and, therefore, reduce the amount of acquisition costs that will be expensed. Accordingly, the Company capitalized $0.1 million of acquisition costs during the three months ended March 31, 2018 and expensed $0.3 million of acquisition costs during the three months ended March 31, 2017 . 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 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 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 Financial Accounting Standards Board issued ASU 2017-12, Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities . The purpose of this updated guidance is to better align a company’s financial reporting for hedging activities with the economic objectives of those activities. ASU 2017-12 is effective for fiscal years beginning after December 15, 2018, with early adoption, including adoption in an interim period, permitted. The Company 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 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 In February 2018, the FASB issued ASU 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. Early adoption is permitted. We are currently assessing the impact this guidance will have on our consolidated financial statements.

Real Estate

Real Estate	3 Months Ended
	Mar. 31, 2018
Acquisition and Disposition of Properties and Discontinued Operations [Abstract]
Real Estate	Real Estate The Company’s consolidated real estate is comprised of the following (in thousands): March 31, 2018 December 31, 2017 Land $ 667,847 $ 658,835 Buildings and improvements 2,444,871 2,406,488 Tenant improvements 136,682 131,850 Construction in progress 21,060 18,642 Properties under capital lease 76,965 76,965 Total 3,347,425 3,292,780 Less: Accumulated depreciation (359,048 ) (339,862 ) Operating real estate, net 2,988,377 2,952,918 Real estate under development, at cost 182,380 173,702 Net investments in real estate $ 3,170,757 $ 3,126,620 Acquisitions and Conversions During the three months ended March 31, 2018 and the year ended December 31, 2017 , the Company acquired the following consolidated retail properties (dollars in thousands): Property and Location Percent Acquired Date of Acquisition Purchase Price Debt Assumed 2018 Acquisitions Core Bedford Green Land Parcel 100% Mar 23, 2018 $ 1,337 $ — Subtotal Core 1,337 — Fund V Trussville Promenade - Trussville, AL 100% Feb 21, 2018 45,259 — Subtotal Fund V 45,259 — Total 2018 Acquisitions $ 46,596 $ — 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 ( Note 1 ). However, all of the 2017 acquisitions and conversions were deemed to be business combinations. For the three months ended March 31, 2018 , the Company capitalized $0.1 million of acquisition costs related to the Funds. The Company expensed $0.3 million of acquisition costs for the three months ended March 31, 2017 , of which $0.2 million related to the Core Portfolio and $0.1 million related to the Funds. 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 three months ended March 31, 2018 and the year ended December 31, 2017 (in thousands): Three Months Ended Year Ended December 31, 2017 Net Assets Acquired Land $ 9,012 $ 48,138 Buildings and improvements 34,064 173,576 Other assets — 84 Acquisition-related intangible assets (in Acquired lease intangibles, net) 6,499 44,269 Acquisition-related intangible liabilities (in Acquired lease intangibles, net) (2,979 ) (11,535 ) Net assets acquired $ 46,596 $ 254,532 Consideration Cash $ 46,171 $ 200,429 Conversion of note receivable — 41,010 Liabilities assumed 425 3,363 Existing interest in previously unconsolidated investment — 4,159 Change in control of previously unconsolidated investment — 5,571 Total Consideration $ 46,596 $ 254,532 Dispositions During the three months ended March 31, 2018 , there were no dispositions of consolidated properties. During the year ended 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 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 rental revenue, expenses and pre-tax income reported within continuing operations for the aforementioned consolidated properties that were sold during the year ended December 31, 2017 were as follows (in thousands): Three Months Ended March 31, 2017 Rental revenues $ 2,840 Expenses (4,803 ) Loss from continuing operations of (1,963 ) Net income attributable to noncontrolling interests 1,405 Net loss attributable to Acadia $ (558 ) Properties Held For Sale At March 31, 2018 and 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 . This property had a net loss of $0.1 million and $0.3 million for the three months ended March 31, 2018 and 2017 , respectively. 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 Three Months Ended March 31, 2018 March 31, 2018 Number of Properties Carrying Value Transfers In Capitalized Costs Transfers Out Number of Properties Carrying Value Core 2 $ 21,897 $ — $ 2,159 $ — 2 $ 24,056 Fund II — 4,908 — (175 ) — — 4,733 Fund III 2 63,939 — 6,431 — 2 70,370 Fund IV 1 82,958 — 263 — 1 83,221 Total 5 $ 173,702 $ — $ 8,678 $ — 5 $ 182,380 During the three months ended March 31, 2018 , the Company did not move any projects into or out of development. In addition to the consolidated projects noted above, the Company had one unconsolidated project remaining in development. 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

Notes Receivable, Net	3 Months Ended
	Mar. 31, 2018
Accounts and Notes Receivable, Net [Abstract]
Notes Receivable, Net	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): March 31, December 31, March 31, 2018 Description 2018 2017 Number Maturity Date Interest Rate Core Portfolio $ 56,475 $ 101,695 2 April 2019 - April 2020 6.0% - 8.1% Fund II 31,978 31,778 1 May 2020 2.5% Fund III 5,256 5,106 1 July 2020 18.0% Fund IV 15,250 15,250 1 February 2021 15.3% $ 108,959 $ 153,829 5 During the three months ended March 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 $0.2 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 ).

Investments in and Advances to

Investments in and Advances to Unconsolidated Affiliates	3 Months Ended
	Mar. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Investments in and Advances to Unconsolidated Affiliates	Investments In and Advances to Unconsolidated Affiliates The Company accounts for its investments in and advances to unconsolidated affiliates primarily under the equity method of accounting as it has the ability to exercise significant influence, but does not have financial or operating control over the investment, which is maintained by each of the unaffiliated partners who co-invest with the Company. The Company’s investments in and advances to unconsolidated affiliates consist of the following (dollars in thousands): Nominal Ownership Interest March 31, 2018 December 31, 2017 Fund Property March 31, 2018 Core: 840 N. Michigan (a) 88.43% $ 69,265 $ 69,846 Renaissance Portfolio 20% 34,294 35,041 Gotham Plaza 49% 29,408 29,416 Town Center (a, b) 75.22% 100,918 78,801 Georgetown Portfolio 50% 3,540 3,479 237,425 216,583 Mervyns I & II: KLA/Mervyn's, LLC (c) 10.5% — — Fund III: Fund III Other Portfolio 90% 161 167 Self Storage Management (d) 95% 206 206 367 373 Fund IV: Broughton Street Portfolio (e) 50% 41,331 48,335 Fund IV Other Portfolio 90% 16,101 20,199 650 Bald Hill Road 90% 13,506 13,609 70,938 82,143 Various Funds: Due from Related Parties (f) 2,254 2,415 Other (g) 556 556 Investments in and advances to unconsolidated affiliates $ 311,540 $ 302,070 Core: Crossroads (h) 49% $ 15,226 $ 15,292 Distributions in excess of income from, $ 15,226 $ 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 have exceeded the Company’s non-recourse investment, therefore the carrying value is zero. (d) Represents a variable interest entity. (e) The Company is entitled to a 15% return on its cumulative capital contribution which was $15.7 million and $15.4 million at March 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 $30.2 million and $36.8 million at March 31, 2018 and December 31, 2017 , respectively. (f) Represents deferred fees. (g) Includes a cost-method investment in Albertson’s ( Note 8 ) and other investments. (h) Distributions have exceeded the Company’s investment; however, the Company recognizes a liability balance as it may be required to fund future obligations of the entity. Core Portfolio Acquisition of Unconsolidated Investment On January 4, 2017, an entity in which the Company owns a 20% noncontrolling interest (the “Renaissance Portfolio”), acquired a 6,200 square foot property in Alexandria, Virginia referred to as (“907 King Street”) for $3.0 million . The Renaissance Portfolio is now a 213,000 square-foot portfolio of 18 mixed-use properties, 16 of which are located in Georgetown, Washington D.C. and two of which are located in Alexandria, Virginia. Brandywine Portfolio, Market Square and Town Center The Company owns an interest in an approximately one million square foot retail portfolio (the “Brandywine Portfolio” joint venture) located in Wilmington, Delaware, which includes two properties referred to as “Market Square” and “Town Center.” Prior to the second quarter of 2016, the Company had a controlling interest in the Brandywine Portfolio, and it was therefore consolidated within the Company’s financial statements. During April 2016, the arrangement with the partners of the Brandywine Portfolio was modified to change the legal ownership from a partnership to a tenancy-in-common interest, as well as to provide certain participating rights to the outside partners. As a result of these modifications, the Company de-consolidated the Brandywine Portfolio and accounted for its interest under the equity method of accounting effective May 1, 2016. Furthermore, as the owners of the Brandywine Portfolio had consistent ownership interests before and after the modification and the underlying net assets were unchanged, the Company reflected the change from consolidation to equity method based upon its historical cost. The Brandywine Portfolio and Market Square ventures do not include the property held by Brandywine Holdings, an entity consolidated by the Company. Additionally, in April 2016, the Company repaid the outstanding balance of $140.0 million of non-recourse debt collateralized by the Brandywine Portfolio and provided a note receivable collateralized by the partners’ tenancy-in-common interest in the Brandywine Portfolio for their proportionate share of the repayment. On May 1, 2017, the Company exchanged $16.0 million of the $153.4 million notes receivable (the “Brandywine Notes Receivable”) ( Note 3 ) plus accrued interest of $0.3 million for one of the partner’s 38.89% tenancy-in-common interests in Market Square. The Company already had a 22.22% interest in Market Square and continued to apply the equity method of accounting for its aggregate 61.11% noncontrolling interest in Market Square and its 22.22% interest in Town Center through November 16, 2017. The incremental investment in Market Square was recorded at $16.3 million and the excess of this amount over the venture’s book value associated with this interest, or $9.8 million , was being amortized over the remaining depreciable lives of the venture’s assets through November 16, 2017. On November 16, 2017, the Company exchanged an additional $16.0 million of Brandywine Notes Receivable plus accrued interest of $0.6 million for the remaining 38.89% interest in Market Square, thereby obtaining a 100% controlling interest in the property. The exchange was deemed to be a business combination and as a result, the property was consolidated and a gain on change of control of $5.6 million was recorded ( Note 2 ). On November 16, 2017, the Company exchanged $60.7 million of the Brandywine Notes Receivable plus accrued interest of $0.9 million for one of the partner’s 38.89% tenancy-in-common interests in Town Center. The incremental investment in Town Center was recorded at $61.6 million and the excess of this amount over the venture’s book value associated with this interest, or $34.5 million , will be amortized over the remaining depreciable lives of the venture’s assets. The Company 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 , will be 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 March 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 Fund II’s cost method investment in Albertson’s supermarkets among other investments. In 2017, the Company received $2.4 million in distributions from Albertson’s and reduced the carrying amount of its investment in Albertson’s to zero , reflecting the remaining $2.0 million as equity in earnings and gains of unconsolidated affiliates in the consolidated statements of income. 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 . At March 31, 2018 , the Broughton Street portfolio had 16 remaining properties. 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 $ 0.3 million and $ 0.4 million for the three months ended March 31, 2018 and 2017 , 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, $ 0.5 million for both the three months ended March 31, 2018 and 2017 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): March 31, December 31, 2018 2017 Combined and Condensed Balance Sheets Assets: Rental property, net $ 509,634 $ 518,900 Real estate under development 24,976 26,681 Investment in unconsolidated affiliates 6,853 6,853 Other assets 95,934 100,901 Total assets $ 637,397 $ 653,335 Liabilities and partners’ equity: Mortgage notes payable $ 405,955 $ 405,652 Other liabilities 60,950 61,932 Partners’ equity 170,492 185,751 Total liabilities and partners’ equity $ 637,397 $ 653,335 Company's share of accumulated equity $ 183,602 $ 185,533 Basis differential 107,347 95,358 Deferred fees, net of portion related to the Company's interest 3,111 3,472 Amounts receivable by the Company 2,254 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 296,314 286,778 Company's share of distributions in excess of income from and investments in unconsolidated affiliates 15,226 15,292 Investments in and advances to unconsolidated affiliates $ 311,540 $ 302,070 Three Months Ended March 31, 2018 2017 Combined and Condensed Statements of Income Total revenues $ 20,156 $ 21,603 Operating and other expenses (5,921 ) (5,866 ) Interest expense (4,874 ) (4,538 ) Depreciation and amortization (6,055 ) (6,449 ) Loss on debt extinguishment — (151 ) (Loss) gain on disposition of properties (418 ) 14,446 Net income attributable to unconsolidated affiliates $ 2,888 $ 19,045 Company’s share of equity in $ 2,267 $ 13,569 Basis differential amortization (583 ) (866 ) Company’s equity in earnings of unconsolidated affiliates $ 1,684 $ 12,703

Other Assets, Net and Accounts

Other Assets, Net and Accounts Payable and Other Liabilities	3 Months Ended
	Mar. 31, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other Assets, net and Accounts Payable and Other Liabilities	Other Assets, Net and Accounts Payable and Other Liabilities Other assets, net and accounts payable and other liabilities are comprised of the following for the periods presented: March 31, December 31, (in thousands) 2018 2017 Other Assets, Net: Lease intangibles, net ( Note 6 ) $ 125,050 $ 127,571 Deferred charges, net (a) 27,730 24,589 Prepaid expenses 17,927 16,838 Other receivables 5,719 11,356 Accrued interest receivable 12,450 11,668 Deposits 4,549 6,296 Due from seller 4,300 4,300 Deferred tax assets 2,141 2,096 Derivative financial instruments ( Note 8 ) 9,958 4,402 Due from related parties 2,397 1,479 Corporate assets 2,287 2,369 Income taxes receivable 2,006 1,995 $ 216,514 $ 214,959 (a) Deferred Charges, Net: Deferred leasing and other costs $ 41,985 $ 41,020 Deferred financing costs 8,634 7,786 50,619 48,806 Accumulated amortization (22,889 ) (24,217 ) Deferred charges, net $ 27,730 $ 24,589 Accounts Payable and Other Liabilities: Lease intangibles, net ( Note 6 ) $ 104,273 $ 104,478 Accounts payable and accrued expenses 59,771 61,420 Deferred income 31,260 31,306 Tenant security deposits, escrow and other 10,412 10,029 Derivative financial instruments ( Note 8 ) 1,238 1,467 Income taxes payable 575 176 Other 1,561 1,176 $ 209,090 $ 210,052
Other Assets, net and Accounts Payable and Other Liabilities	Other Assets, Net and Accounts Payable and Other Liabilities Other assets, net and accounts payable and other liabilities are comprised of the following for the periods presented: March 31, December 31, (in thousands) 2018 2017 Other Assets, Net: Lease intangibles, net ( Note 6 ) $ 125,050 $ 127,571 Deferred charges, net (a) 27,730 24,589 Prepaid expenses 17,927 16,838 Other receivables 5,719 11,356 Accrued interest receivable 12,450 11,668 Deposits 4,549 6,296 Due from seller 4,300 4,300 Deferred tax assets 2,141 2,096 Derivative financial instruments ( Note 8 ) 9,958 4,402 Due from related parties 2,397 1,479 Corporate assets 2,287 2,369 Income taxes receivable 2,006 1,995 $ 216,514 $ 214,959 (a) Deferred Charges, Net: Deferred leasing and other costs $ 41,985 $ 41,020 Deferred financing costs 8,634 7,786 50,619 48,806 Accumulated amortization (22,889 ) (24,217 ) Deferred charges, net $ 27,730 $ 24,589 Accounts Payable and Other Liabilities: Lease intangibles, net ( Note 6 ) $ 104,273 $ 104,478 Accounts payable and accrued expenses 59,771 61,420 Deferred income 31,260 31,306 Tenant security deposits, escrow and other 10,412 10,029 Derivative financial instruments ( Note 8 ) 1,238 1,467 Income taxes payable 575 176 Other 1,561 1,176 $ 209,090 $ 210,052

Lease Intangibles

Lease Intangibles	3 Months Ended
	Mar. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Lease Intangibles	Lease Intangibles Upon acquisitions of real estate, the Company assesses the fair value of acquired assets (including land, buildings and improvements, and identified intangibles such as above- and below-market leases, including below- market options and acquired in-place leases) and assumed liabilities. The lease intangibles are amortized over the remaining terms of the respective leases, including option periods where applicable. Intangible assets and liabilities are summarized as follows (in thousands): March 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 $ 199,740 $ (81,262 ) $ 118,478 $ 193,821 $ (72,749 ) $ 121,072 Above-market rent 17,366 (10,794 ) 6,572 16,786 (10,287 ) 6,499 $ 217,106 $ (92,056 ) $ 125,050 $ 210,607 $ (83,036 ) $ 127,571 Amortizable Intangible Liabilities Below-market rent $ (150,211 ) $ 46,560 $ (103,651 ) $ (147,232 ) $ 43,391 $ (103,841 ) Above-market ground lease (671 ) 49 (622 ) (671 ) 34 (637 ) $ (150,882 ) $ 46,609 $ (104,273 ) $ (147,903 ) $ 43,425 $ (104,478 ) During the three months ended March 31, 2018 , the Company acquired in-place lease intangible assets of $5.9 million , above-market rents of $0.6 million , and below-market rents of $3.0 million with weighted-average useful lives of 4.6 , 1.1 , and 25.7 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 March 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) 2018 (Remainder) $ 6,219 $ (19,544 ) $ 44 $ (13,281 ) 2019 9,596 (23,316 ) 58 (13,662 ) 2020 8,830 (17,389 ) 58 (8,501 ) 2021 7,650 (12,760 ) 58 (5,052 ) 2022 7,353 (8,949 ) 58 (1,538 ) Thereafter 57,431 (36,520 ) 346 21,257 Total $ 97,079 $ (118,478 ) $ 622 $ (20,777 )

Debt

Debt	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
Debt	Debt A summary of the Company’s consolidated indebtedness is as follows (dollars in thousands): Interest Rate at March 31, December 31, Maturity Date at March 31, December 31, 2018 2017 March 31, 2018 2018 2017 Mortgages Payable Core Fixed Rate 3.88%-6.00% 3.88%-5.89% February 2024 - April 2035 $ 179,475 $ 179,870 Core Variable Rate - Swapped (a) 3.41%-3.77% 1.71%-3.77% January 2023 - June 2026 33,323 74,152 Total Core Mortgages Payable 212,798 254,022 Fund II Fixed Rate 1.00%-4.75% 1.00%-4.75% August 2019 - August 2042 205,262 205,262 Fund II Variable Rate - Swapped (a) 2.88% 2.88% November 2021 19,503 19,560 Total Fund II Mortgages Payable 224,765 224,822 Fund III Variable Rate Prime+0.50%-LIBOR+4.65% Prime+0.50%-LIBOR+4.65% May 2018 - December 2021 70,344 65,866 Fund IV Fixed Rate 3.40%-4.50% 3.40%-4.50% October 2025-June 2026 10,503 10,503 Fund IV Variable Rate LIBOR+1.70%-LIBOR+3.95% LIBOR+1.70%-LIBOR+3.95% April 2018 - August 2021 249,954 250,584 Fund IV Variable Rate - Swapped (a) 3.67%-4.23% 1.78%-2.11% May 2019 - December 2022 86,517 86,851 Total Fund IV Mortgages Payable 346,974 347,938 Fund V Variable Rate LIBOR+2.15%-LIBOR+2.25% LIBOR+2.25% October 2020 - January 2021 51,506 28,613 Fund V Variable Rate - Swapped (a) 4.61% — February 2021 16,900 — Total Fund V Mortgage Payable 68,406 28,613 Net unamortized debt issuance costs (12,590 ) (12,943 ) Unamortized premium 830 856 Total Mortgages Payable $ 911,527 $ 909,174 Unsecured Notes Payable Core Variable Rate Unsecured (a) 2.49%-4.05% 1.24%-3.77% March 2023 $ 350,000 $ 300,000 Fund II Unsecured Notes Payable LIBOR+1.65% LIBOR+1.40% September 2020 31,500 31,500 Fund IV Term Loan/Subscription Facility LIBOR+1.65%-LIBOR+2.75% LIBOR+1.65%-LIBOR+2.75% December 2018- October 2019 40,825 40,825 Fund V Subscription Facility LIBOR+1.60% LIBOR+1.60% May 2020 108,100 103,300 Net unamortized debt issuance costs (669 ) (1,890 ) Total Unsecured Notes Payable $ 529,756 $ 473,735 Unsecured Line of Credit Core Unsecured Line of Credit — LIBOR+1.40% — $ — $ 18,048 Core Unsecured Line of Credit - Swapped (a) 2.59%-4.15% 1.24%-3.77% March 2022 14,000 23,452 Total Unsecured Line of Credit $ 14,000 $ 41,500 Total Debt - Fixed Rate (b) $ 915,483 $ 899,650 Total Debt - Variable Rate (c) 552,229 538,736 Total Debt 1,467,712 1,438,386 Net unamortized debt issuance costs (13,259 ) (14,833 ) Unamortized premium 830 856 Total Indebtedness $ 1,455,283 $ 1,424,409 __________ (a) At March 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; PRIME + 0.50% to LIBOR + 4.65% for Fund III variable-rate debt; LIBOR + 1.85% to LIBOR + 2.25% for Fund IV variable-rate debt, LIBOR + 2.20% for Fund V and LIBOR + 1.25% for Core variable-rate unsecured term loans. (b) Includes $520.2 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”), and a $350.0 million senior unsecured term loan (the “Term Loan”). The Credit Facility refinanced the Company’s existing $300.0 million credit facility (comprised of the $150.0 million Core unsecured revolving line of credit and the $150.0 million term loan), $150.0 million in Core unsecured term loans 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 three months ended March 31, 2018 , the Company obtained two new non-recourse Fund mortgages totaling $39.8 million with a weighted-average interest rate of LIBOR + 2.17% collateralized by two properties and maturing in 2021. The Company entered into interest rate swap contracts to effectively fix the variable portion of the interest rates of one of these obligations with a notional value of $16.9 million at an interest rate of 2.41% . During the three months ended March 31, 2018 , the Company repaid one Core mortgage in full, which had a total balance of $40.4 million and a weighted-average interest rate of LIBOR + 1.65% , and made scheduled principal payments of $1.9 million . At March 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 amounted to $26.3 million and was in default at March 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 aggregating approximately $32.9 million . The Company’s management believes that the mortgage is not recourse to the Company and that the suit is without merit. Unsecured Notes Payable Unsecured notes payable for which total availability was $65.5 million and $70.3 million at March 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 March 31, 2018 and December 31, 2017 . 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% . • 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 $31.5 million at each of March 31, 2018 and December 31, 2017 . Total availability was $8.5 million , at each of March 31, 2018 and December 31, 2017 . • At Fund IV there are a $41.8 million bridge facility and a $21.5 million subscription line. The outstanding balance of the Fund IV bridge facility was $40.8 million at each of March 31, 2018 and December 31, 2017 . Total availability was $1.0 million at each of March 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 March 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 $108.1 million and $41.9 million , respectively at March 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 $123.7 million and $96.2 million available under its $150.0 million Core unsecured revolving lines of credit reflecting borrowings of $14.0 million and $41.5 million and letters of credit of $12.3 million at each of March 31, 2018 and December 31, 2017 . At March 31, 2018 , 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 March 31, 2018 are as follows (in thousands): Year Ending December 31, 2018 (Remainder) $ 52,396 2019 207,952 2020 494,608 2021 113,012 2022 62,529 Thereafter 537,215 1,467,712 Unamortized fair market value of assumed debt 830 Net unamortized debt issuance costs (13,259 ) Total indebtedness $ 1,455,283 See Note 4 for information about liabilities of the Company’s unconsolidated affiliates.

Financial Instruments and Fair

Financial Instruments and Fair Value Measurements	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Financial Instruments and Fair Value Measurements	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. — 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 three months ended March 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): March 31, 2018 December 31, 2017 Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Assets Money Market Funds $ 105 $ — $ — $ 3 $ — $ — Derivative financial instruments — 9,958 — — 4,402 — Liabilities Derivative financial instruments — 1,238 — — 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 three months ended March 31, 2018 or 2017. Derivative Financial Instruments The Company had the following interest rate swaps for the periods presented (dollars in thousands): Aggregate Strike Rate Balance Sheet Location Fair Value Derivative Instrument Effective Date Maturity Date Low High March 31, 2018 December 31, 2017 Core Interest Rate Swaps $ 69,864 October 2011 - March 2018 July 2018 - March 2028 2.9% — 3.77% Other Liabilities $ (1,238 ) $ (1,438 ) Interest Rate Swaps 336,823 February 2013 - December 2017 November 2018 - July 2027 1.24% — 3.77% Other Assets 8,458 4,076 $ 406,687 $ 7,220 $ 2,638 Fund II Interest Rate Swap $ 19,503 October 2014 November 2021 2.88% — 2.88% Other Assets $ 155 $ — Interest Rate Swaps — October 2014 November 2021 2.88% — 2.88% Other Liabilities — (29 ) Interest Rate Cap 29,500 April 2013 April 2018 4.00% — 4.00% Other Assets — — $ 49,003 $ 155 $ (29 ) Fund III Interest Rate Cap $ 58,000 December 2016 January 2020 3.00% — 3.00% Other Assets $ 48 $ 14 Fund IV Interest Rate Swaps $ 86,517 May 2014 - November 2017 May 2019 - April 2022 1.78% — 2.11% Other Assets $ 1,222 $ 295 Interest Rate Caps 108,900 July 2016 - November 2016 August 2019 - December 2019 3.00% — 3.00% Other Assets 65 17 $ 195,417 $ 1,287 $ 312 Fund V Interest Rate Swaps $ 16,900 January 2018 February 2021 2.41% — 2.41% Other Assets $ 10 $ — Total asset derivatives $ 9,958 $ 4,402 Total liability derivatives $ (1,238 ) $ (1,467 ) 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 $1.1 million included in accumulated other comprehensive (loss) income related to derivatives will be reclassified to interest expense in the 2018 results of operation. As of March 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): Three Months Ended March 31, 2018 2017 Amount of (loss) income related to the effective portion recognized in other comprehensive income $ 5,653 $ 118 Amount of loss related to the effective portion subsequently reclassified to earnings — — Amount of gain (loss) related to the ineffective portion and amount excluded from effectiveness testing — — Credit Risk-Related Contingent Features The Company has agreements with each of its Swap counterparties that contain a provision whereby if the Company defaults on certain of its unsecured indebtedness the Company could also be declared in default on its swaps, resulting in an acceleration of payment under the swaps. Other Financial Instruments The Company’s other financial instruments had the following carrying values and fair values as of the dates shown (dollars in thousands): March 31, 2018 December 31, 2017 Level Carrying Estimated Carrying Estimated Notes Receivable (a) 3 $ 108,959 $ 105,985 $ 153,829 $ 151,712 Mortgage and Other Notes Payable (a) 3 923,287 912,968 921,261 921,891 Investment in non-traded equity securities (b) 3 — 22,824 — 22,824 Unsecured notes payable and Unsecured line of credit (c) 2 544,425 544,506 517,125 515,330 __________ (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 March 31, 2018 .

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The Company is involved in various matters of litigation arising in the normal course of business. While the Company is unable to predict with certainty the amounts involved, the Company’s management and counsel are of the opinion that, when such litigation is resolved, the Company’s resulting liability, if any, will not have a significant effect on the Company’s consolidated financial position, results of operations, or liquidity. The Company's policy is to accrue legal expenses as they are incurred. Commitments and Guaranties In conjunction with the development and expansion of various properties, the Company has entered into agreements with general contractors for the construction or development of properties aggregating approximately $87.1 million and $92.2 million as of March 31, 2018 and December 31, 2017 , respectively. At each of March 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, Noncontro

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income	3 Months Ended
	Mar. 31, 2018
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]
Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income	Shareholders’ Equity, Noncontrolling Interests and Other Comprehensive Income Common Shares and Units The Company completed the following transactions in its common shares during the three months ended March 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 $2.2 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 1,304,194 shares for $32.0 million during the three months ended March 31, 2018 , and did no t repurchase any shares during the year ended December 31, 2017 . As of March 31, 2018 , management may repurchase up to approximately $168.0 million of the Company’s outstanding Common Shares under this program. During April 2018, the Company repurchased additional shares under this program as discussed in Note 15 . Dividends and Distributions 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 three months ended March 31, 2018 and 2017 (in thousands): Gains or Losses on Derivative Instruments Balance at January 1, 2018 $ 2,614 Other comprehensive income before reclassifications 5,653 Reclassification of realized interest on swap agreements 363 Net current period other comprehensive income 6,016 Net current period other comprehensive income attributable to noncontrolling interests (1,254 ) Balance at March 31, 2018 $ 7,376 Balance at January 1, 2017 $ (798 ) Other comprehensive income before reclassifications 118 Reclassification of realized interest on swap agreements 963 Net current period other comprehensive income 1,081 Net current period other comprehensive loss attributable to noncontrolling interests 155 Balance at March 31, 2017 $ 438 Noncontrolling Interests The following table summarizes the change in the noncontrolling interests for the three months ended March 31, 2018 and 2017 (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 $0.27 per Common OP Unit (1,721 ) — (1,721 ) Net income (loss) for the period January 1 through March 31, 2018 612 (12,191 ) (11,579 ) Conversion of 36,126 Common OP Units to (642 ) — (642 ) Other comprehensive income - unrealized loss 274 886 1,160 Reclassification of realized interest expense on swap agreements 10 84 94 Noncontrolling interest distributions — (695 ) (695 ) Employee Long-term Incentive Plan Unit Awards 3,716 — 3,716 Rebalancing adjustment (c) 1,225 — 1,225 Balance at March 31, 2018 $ 106,395 $ 533,603 $ 639,998 Balance at January 1, 2017 $ 95,422 $ 494,126 $ 589,548 Distributions declared of $0.26 per Common OP Unit (1,617 ) — (1,617 ) Net income for the period January 1 through March 31, 2017 1,062 3,278 4,340 Conversion of 24,860 Common OP Units to Common Shares (438 ) — (438 ) Other comprehensive income - unrealized loss 21 (317 ) (296 ) Reclassification of realized interest expense on swap agreements 49 92 141 Noncontrolling interest contributions — 20,269 20,269 Noncontrolling interest distributions — (3,822 ) (3,822 ) Employee Long-term Incentive Plan Unit Awards 4,141 — 4,141 Rebalancing adjustment (c) 5,693 — 5,693 Balance at March 31, 2017 $ 104,333 $ 513,626 $ 617,959 __________ (a) Noncontrolling interests in the Operating Partnership are comprised of (i) the limited partners’ 3,328,873 Common OP Units at March 31, 2018 and December 31, 2017 ; (ii) 188 Series A Preferred OP Units at March 31, 2018 and December 31, 2017 ; (iii) 136,593 Series C Preferred OP Units at March 31, 2018 and December 31, 2017 ; and (iv) 2,619,872 and 2,274,147 LTIP units as of at March 31, 2018 and December 31, 2017 , respectively, as discussed in Share Incentive Plan ( Note 13 ). Distributions declared for Preferred OP Units are reflected in net income in the table above. (b) Noncontrolling interests in partially-owned affiliates comprise third-party interests in Funds II, III, IV and V, and Mervyns I and II, and six other subsidiaries. (c) 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 three months ended March 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 March 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 March 31, 2018 , 5,000 Series C Preferred OP Units were converted into 17,165 Common OP Units and then into Common Shares.

Leases

Leases	3 Months Ended
	Mar. 31, 2018
Leases [Abstract]
Leases	Leases Operating Leases The Company is engaged in the operation of shopping centers and other retail properties that are either owned or, with respect to certain shopping centers, operated under long-term ground leases that expire at various dates through June 20, 2066, with renewal options. Space in the shopping centers is leased to tenants pursuant to agreements that provide for terms ranging generally from one month to ninety-nine years and generally provide for additional rents based on certain operating expenses as well as tenants’ sales volumes. The Company leases land at seven of its shopping centers, which are accounted for as operating leases and generally provide the Company with renewal options. Ground rent expense was $0.4 million and $0.8 million (including capitalized ground rent at a property under development of $0.2 million and $0.1 million ) for the three months ended March 31, 2018 and 2017, respectively. The leases terminate at various dates between 2020 and 2066. These leases provide the Company with options to renew for additional terms aggregating from 25 to 71 years. The Company also leases space for its corporate office. Office rent expense under this lease was $0.2 million for each of the three months ended March 31, 2018 and 2017. Capital Lease During 2016, the Company entered into a 49 -year master lease at 991 Madison Avenue, which is accounted for as a capital lease. During each of the three months ended March 31, 2018 and 2017, payments for this lease totaled $0.6 million . The lease was initially valued at $76.6 million, which represents the total discounted payments to be made under the lease. The property under the capital lease is included in Note 2 . Lease Obligations The scheduled future minimum (i) rental revenues from rental properties under the terms of all non-cancelable tenant leases, assuming no new or renegotiated leases or option extensions for such premises and (ii) rental payments under the terms of all non-cancelable operating and capital leases in which the Company is the lessee, principally for office space and ground leases, as of March 31, 2018 , are summarized as follows (in thousands): Year Ending December 31, Minimum Rental Revenues Minimum Rental Payments 2018 (Remainder) $ 125,069 $ 4,546 2019 169,873 4,565 2020 155,238 4,256 2021 135,874 4,364 2022 116,972 4,400 Thereafter 527,122 183,911 Total $ 1,230,148 $ 206,042 A ground lease expiring during 2078 provides the Company with an option to purchase the underlying land during 2031. If the Company does not exercise the option, the rents that will be due are based on future values and as such are not determinable at this time. Accordingly, the above table does not include rents for this lease beyond 2031. During the three months ended March 31, 2018 and 2017, no single tenant collectively comprised more than 10% of the Company’s consolidated total revenues.

Segment Reporting

Segment Reporting	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Segment Reporting	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 Three Months Ended March 31, 2018 Core Portfolio Funds Structured Financing Unallocated Total Revenues $ 41,628 $ 21,496 $ — $ — $ 63,124 Depreciation and amortization (15,498 ) (13,078 ) — — (28,576 ) Property operating expenses, other operating and real estate taxes (10,894 ) (8,483 ) — — (19,377 ) General and administrative expenses — — — (8,470 ) (8,470 ) Operating income (loss) 15,236 (65 ) — (8,470 ) 6,701 Interest income — — 3,737 — 3,737 Equity in earnings of unconsolidated affiliates inclusive of gains on disposition of properties 1,426 258 — — 1,684 Interest expense (6,502 ) (9,388 ) — — (15,890 ) Income tax provision — — — (392 ) (392 ) Net income (loss) 10,160 (9,195 ) 3,737 (8,862 ) (4,160 ) Net income (loss) attributable to noncontrolling interests (73 ) 11,652 — — 11,579 Net income attributable to Acadia $ 10,087 $ 2,457 $ 3,737 $ (8,862 ) $ 7,419 Real estate at cost $ 2,042,280 $ 1,487,525 $ — $ — $ 3,529,805 Total assets $ 2,283,451 $ 1,546,566 $ 108,959 $ — $ 3,938,976 Cash paid for acquisition of real estate $ 1,337 $ 44,834 $ — $ — $ 46,171 Cash paid for development and property improvement costs $ 5,946 $ 12,190 $ — $ — $ 18,136 As of or for the Three Months Ended March 31, 2017 Core Portfolio Funds Structured Financing Unallocated Total Revenues $ 44,446 $ 17,553 $ — $ — $ 61,999 Depreciation and amortization (16,439 ) (8,097 ) — — (24,536 ) Property operating expenses, other operating and real estate taxes (12,853 ) (6,244 ) — — (19,097 ) General and administrative expenses — — — (8,469 ) (8,469 ) Operating income 15,154 3,212 — (8,469 ) 9,897 Interest income — — 8,984 — 8,984 Equity in earnings of unconsolidated affiliates inclusive of gains on disposition of properties 560 12,143 — — 12,703 Interest expense (7,155 ) (4,333 ) — — (11,488 ) Income tax provision — — — (125 ) (125 ) Net income 8,559 11,022 8,984 (8,594 ) 19,971 Net income attributable to noncontrolling interests (432 ) (3,908 ) — — (4,340 ) Net income attributable to Acadia $ 8,127 $ 7,114 $ 8,984 $ (8,594 ) $ 15,631 Real estate at cost $ 1,983,365 $ 1,480,201 $ — $ — $ 3,463,566 Total assets $ 2,246,037 $ 1,498,045 $ 276,507 $ — $ 4,020,589 Cash paid for acquisition of real estate $ — $ 34,688 $ — $ — $ 34,688 Cash paid for development and property improvement costs $ 996 $ 26,019 $ — $ — $ 27,015

Share Incentive and Other Compe

Share Incentive and Other Compensation	3 Months Ended
	Mar. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share Incentive and Other Compensation	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 March 31, 2018 a total of 1,223,815 shares remained available to be issued under the Share Incentive Plan. Restricted Shares and LTIP Units During the three months ended March 31, 2018 , the Company issued 381,821 LTIP Units and 5,768 Restricted Share Units to employees of the Company pursuant to the Share Incentive Plan. These awards were measured at their fair value on the grant date, based on a valuation provided by an independent third-party appraiser 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. The total value of the above Restricted Share Units and LTIP Units as of the grant date was $ 10.6 million . Total long-term incentive compensation expense, including the expense related to the Share Incentive Plan, was $2.2 million and $1.9 million for the three months ended March 31, 2018 and 2017, respectively and is recorded in General and Administrative on the Consolidated Statements of Income. In addition, members of the Board of Trustees (the “Board”) have been issued shares and units under the Share Incentive Plan. During 2017, the Company issued 11,814 Restricted Shares and 11,105 LTIP Units to Trustees of the Company in connection with Trustee fees. Vesting with respect to 3,864 of the Restricted Shares and 5,805 of the LTIP Units will be on the first anniversary of the date of issuance and 7,950 of the Restricted Shares and 5,300 of the LTIP Units vest over three years with 33% vesting on each of the next three anniversaries of the issuance date. The Restricted Shares do not carry voting rights or other rights of Common Shares until vesting and may not be transferred, assigned or pledged until the recipients have a vested non-forfeitable right to such shares. Dividends are not paid currently on unvested Restricted Shares, but are paid cumulatively from the issuance date through the applicable vesting date of such Restricted Shares. Total trustee fee expense, including the expense related to the Share Incentive Plan, was $0.3 million for each of the three months ended March 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 March 31, 2018 . Compensation expense of $0 million and $ 0.3 million was recognized for the three months ended March 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 Common Restricted Weighted LTIP Units Weighted Unvested at January 1, 2017 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 5,768 25.96 381,821 27.28 Vested (12,784 ) 31.21 (288,913 ) 30.34 Forfeited (47 ) 35.37 — — Unvested at March 31, 2018 34,264 $ 25.14 1,003,007 $ 27.30 The weighted-average grant date fair value for Restricted Shares and LTIP Units granted for the three months ended March 31, 2018 and the year ended December 31, 2017 were $27.26 and $31.69 , respectively. As of March 31, 2018 , there was $21.0 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 1.9 years. The total fair value of Restricted Shares that vested for each of the three months ended March 31, 2018 and the year ended December 31, 2017 , was $0.7 million . The total fair value of LTIP Units that vested during the three months ended March 31, 2018 and the year ended December 31, 2017 , was $8.8 million and $7.3 million , respectively. Other Plans On a combined basis, the Company incurred a total of $0.1 million related to the following employee benefit plans for each of the three months ended March 31, 2018 and 2017, 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 943 and 841 Common Shares were purchased by employees under the Purchase Plan., for each of the three months ended March 31, 2018 and 2017, respectively. Deferred Share Plan During May of 2006, the Company adopted a Trustee Deferral and Distribution Election, under which the participating Trustees earn deferred compensation. Employee 401(k) Plan The Company maintains a 401(k) plan for employees under which the Company currently matches 50% of a plan participant’s contribution up to 6% of the employee’s annual salary. A plan participant may contribute up to a maximum of 15% of their compensation, up to $18,000 , for the year ending December 31, 2018.

Earnings Per Common Share

Earnings Per Common Share	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Earnings Per Common Share	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 , Note 15 ). 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. Three Months Ended March 31, (dollars in thousands) 2018 2017 Numerator: Net income attributable to Acadia $ 7,419 $ 15,631 Less: net income attributable to participating securities (44 ) (162 ) Income from continuing operations net of income $ 7,375 $ 15,469 Denominator: Weighted average shares for basic earnings per share 83,434,083 83,634,727 Effect of dilutive securities: Employee unvested restricted shares 4,394 10,730 Denominator for diluted earnings per share 83,438,477 83,645,457 Basic and diluted earnings per Common Share from $ 0.09 $ 0.18 Anti-Dilutive Shares Excluded from Denominator: Series A Preferred OP Units 188 188 Series A Preferred OP Units - Common share equivalent 25,067 25,067 Series C Preferred OP Units 136,593 141,593 Series C Preferred OP Units - Common share equivalent 474,278 471,035

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Disposition On April 17, 2018, Fund II sold its Sherman Avenue property, which was classified as held for sale at March 31, 2018 ( Note 2 ), for $26.0 million . Share Repurchases From April 1, 2018 through April 30, 2018, the Company repurchased 936,541 of its outstanding shares for $21.8 million pursuant to its share repurchase plan ( Note 10 ). Through April 30, 2018, the Company has repurchased 2,240,735 shares totaling $53.8 million under the plan . Distributions On April 23, 2018, Fund II made a $15.0 million recallable capital distribution to investors as a result of the sale of its Sherman Avenue property, of which the Operating Partnership’s share was $4.3 million .

Organization, Basis of Presen26

Organization, Basis of Presentation and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Segments	Segments At March 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. Each property is considered a separate operating segment; however, each property on a stand-alone basis represents less than 10% of revenues, profit or loss, and assets of the combined reported operating segment and meets the majority of the aggregations criteria under the applicable standard.
Principles of Consolidation	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. The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information and with the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”). Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. Operating results for the interim periods presented are not necessarily indicative of the results that may be expected for the full fiscal year. The information furnished in the accompanying consolidated financial statements reflects all adjustments that, in the opinion of management, are necessary for a fair presentation of the aforementioned consolidated financial statements for the interim periods. Such adjustments consisted of normal recurring items. These consolidated financial statements should be read in conjunction with the Company’s 2017 Annual Report on Form 10-K, as filed with the SEC on February 27, 2018.
Use of Estimates	Use of Estimates GAAP requires the Company’s management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. The most significant assumptions and estimates relate to the valuation of real estate, depreciable lives, revenue recognition and the collectability of notes receivable and rents receivable. Application of these estimates and assumptions requires the exercise of judgment as to future uncertainties and, as a result, actual results could differ from these estimates.
Recently Issued Accounting Pronouncements	Recently Adopted Accounting Pronouncements In May 2014, the FASB issued Accounting Standards Update (“ASU”) No. 2014-09 , Revenue from Contracts with Customers. ASU 2014-09 is a comprehensive new revenue recognition model requiring a company to recognize revenue to depict the transfer of goods or services to a customer at an amount reflecting the consideration it expects to receive in exchange for those goods or services. ASU 2014-09 does not apply to the Company’s lease revenues, but will apply to reimbursed tenant costs. Additionally, this guidance modifies disclosures regarding the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. In August 2015, the FASB issued ASU 2015-14, which defers the effective date of ASU 2014-09 for all entities by one year, until years beginning in 2018, with early adoption permitted but not before 2017. Entities may adopt ASU 2014-09 using either a full retrospective approach reflecting the application of the standard in each prior reporting period with the option to elect certain practical expedients or a modified retrospective approach with the cumulative effect, recognized at the date of adoption. Substantially all of the Company’s revenue is derived from its leases and therefore falls outside of the scope of this guidance. The Company implemented the standard 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 Company’s revenue recognition. However, the recognition of gains on sales of properties may be impacted prospectively under limited circumstances under which collectability may not be reasonably assured or if the Company has continuing involvement with a sold property. In August 2016, the FASB issued ASU No. 2016-15 , Statement of Cash Flows – Classification of Certain Cash Receipts and Cash Payments. ASU 2016-15 provides guidance on certain specific cash flow issues, including, but not limited to, debt prepayment or extinguishment costs, contingent consideration payments made after a business combination and distributions received from equity method investees. ASU 2016-15 is effective for periods beginning after December 15, 2017, with early adoption permitted and shall be applied retrospectively where practicable. The Company adopted ASU 2016-15 effective January 1, 2018 and elected the “cumulative distribution approach” whereby distributions received from equity method investments would be classified as cash flows from operations to the extent of equity earnings and then as cash flows from investing activities thereafter. Upon the adoption, the Company reclassified $7.3 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 three months ended March 31, 2017 . In November 2016, the FASB issued ASU 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. ASU 2016-18 is effective for public business entities in fiscal years beginning after December 15, 2017, with early adoption permitted. The Company adopted this guidance effective January 1, 2018. Upon the adoption, the Company reclassified $1.0 million of its cash inflows from operating activities to change in cash and restricted cash in its historical presentation of cash flows for the three months ended March 31, 2017 . 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. It is expected that the new standard will reduce the number of future real estate acquisitions that will be accounted for as business combinations and, therefore, reduce the amount of acquisition costs that will be expensed. Accordingly, the Company capitalized $0.1 million of acquisition costs during the three months ended March 31, 2018 and expensed $0.3 million of acquisition costs during the three months ended March 31, 2017 . 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 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 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 Financial Accounting Standards Board issued ASU 2017-12, Derivatives and Hedging: Targeted Improvements to Accounting for Hedging Activities . The purpose of this updated guidance is to better align a company’s financial reporting for hedging activities with the economic objectives of those activities. ASU 2017-12 is effective for fiscal years beginning after December 15, 2018, with early adoption, including adoption in an interim period, permitted. The Company 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 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 In February 2018, the FASB issued ASU 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. Early adoption is permitted. We are currently assessing the impact this guidance will have on our consolidated financial statements.

Organization, Basis of Presen27

Organization, Basis of Presentation and Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
General terms and operating partnership's equity interests	The following table summarizes the general terms and Operating Partnership’s equity interests in the Funds and Mervyns II (dollars in millions): Entity Formation Date Operating Partnership Share of Capital Capital Called as of March 31, 2018 Unfunded Commitment Equity Interest Held By Operating Partnership (a) Preferred Return Total Distributions as of March 31, 2018 (b) Fund II and Mervyns II 6/2004 28.33% $ 347.1 $ — 28.33% 8% $ 131.6 Fund III 5/2007 24.54% 411.5 38.5 24.54% 6% 551.9 Fund IV 5/2012 23.12% 412.7 117.3 23.12% 6% 131.5 Fund V 8/2016 20.10% 45.8 474.2 20.10% 6% — __________ (a) Amount represents the current economic ownership at March 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.

Real Estate (Tables)

Real Estate (Tables)	3 Months Ended
	Mar. 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): March 31, 2018 December 31, 2017 Land $ 667,847 $ 658,835 Buildings and improvements 2,444,871 2,406,488 Tenant improvements 136,682 131,850 Construction in progress 21,060 18,642 Properties under capital lease 76,965 76,965 Total 3,347,425 3,292,780 Less: Accumulated depreciation (359,048 ) (339,862 ) Operating real estate, net 2,988,377 2,952,918 Real estate under development, at cost 182,380 173,702 Net investments in real estate $ 3,170,757 $ 3,126,620
Schedule of Business Acquisitions, by Acquisition	The following table summarizes the allocation of the purchase price of properties acquired during the three months ended March 31, 2018 and the year ended December 31, 2017 (in thousands): Three Months Ended Year Ended December 31, 2017 Net Assets Acquired Land $ 9,012 $ 48,138 Buildings and improvements 34,064 173,576 Other assets — 84 Acquisition-related intangible assets (in Acquired lease intangibles, net) 6,499 44,269 Acquisition-related intangible liabilities (in Acquired lease intangibles, net) (2,979 ) (11,535 ) Net assets acquired $ 46,596 $ 254,532 Consideration Cash $ 46,171 $ 200,429 Conversion of note receivable — 41,010 Liabilities assumed 425 3,363 Existing interest in previously unconsolidated investment — 4,159 Change in control of previously unconsolidated investment — 5,571 Total Consideration $ 46,596 $ 254,532 During the three months ended March 31, 2018 and the year ended December 31, 2017 , the Company acquired the following consolidated retail properties (dollars in thousands): Property and Location Percent Acquired Date of Acquisition Purchase Price Debt Assumed 2018 Acquisitions Core Bedford Green Land Parcel 100% Mar 23, 2018 $ 1,337 $ — Subtotal Core 1,337 — Fund V Trussville Promenade - Trussville, AL 100% Feb 21, 2018 45,259 — Subtotal Fund V 45,259 — Total 2018 Acquisitions $ 46,596 $ — 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 Property Dispositions	During the three months ended March 31, 2018 , there were no dispositions of consolidated properties. During the year ended 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 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	The aggregate rental revenue, expenses and pre-tax income reported within continuing operations for the aforementioned consolidated properties that were sold during the year ended December 31, 2017 were as follows (in thousands): Three Months Ended March 31, 2017 Rental revenues $ 2,840 Expenses (4,803 ) Loss from continuing operations of (1,963 ) Net income attributable to noncontrolling interests 1,405 Net loss attributable to Acadia $ (558 )
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 Three Months Ended March 31, 2018 March 31, 2018 Number of Properties Carrying Value Transfers In Capitalized Costs Transfers Out Number of Properties Carrying Value Core 2 $ 21,897 $ — $ 2,159 $ — 2 $ 24,056 Fund II — 4,908 — (175 ) — — 4,733 Fund III 2 63,939 — 6,431 — 2 70,370 Fund IV 1 82,958 — 263 — 1 83,221 Total 5 $ 173,702 $ — $ 8,678 $ — 5 $ 182,380

Notes Receivable, Net (Tables)

Notes Receivable, Net (Tables)	3 Months Ended
	Mar. 31, 2018
Accounts and Notes Receivable, Net [Abstract]
Schedule of Notes Receivable	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): March 31, December 31, March 31, 2018 Description 2018 2017 Number Maturity Date Interest Rate Core Portfolio $ 56,475 $ 101,695 2 April 2019 - April 2020 6.0% - 8.1% Fund II 31,978 31,778 1 May 2020 2.5% Fund III 5,256 5,106 1 July 2020 18.0% Fund IV 15,250 15,250 1 February 2021 15.3% $ 108,959 $ 153,829 5

Investments in and Advances t30

Investments in and Advances to Unconsolidated Affiliates (Tables)	3 Months Ended
	Mar. 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 March 31, 2018 December 31, 2017 Fund Property March 31, 2018 Core: 840 N. Michigan (a) 88.43% $ 69,265 $ 69,846 Renaissance Portfolio 20% 34,294 35,041 Gotham Plaza 49% 29,408 29,416 Town Center (a, b) 75.22% 100,918 78,801 Georgetown Portfolio 50% 3,540 3,479 237,425 216,583 Mervyns I & II: KLA/Mervyn's, LLC (c) 10.5% — — Fund III: Fund III Other Portfolio 90% 161 167 Self Storage Management (d) 95% 206 206 367 373 Fund IV: Broughton Street Portfolio (e) 50% 41,331 48,335 Fund IV Other Portfolio 90% 16,101 20,199 650 Bald Hill Road 90% 13,506 13,609 70,938 82,143 Various Funds: Due from Related Parties (f) 2,254 2,415 Other (g) 556 556 Investments in and advances to unconsolidated affiliates $ 311,540 $ 302,070 Core: Crossroads (h) 49% $ 15,226 $ 15,292 Distributions in excess of income from, $ 15,226 $ 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 have exceeded the Company’s non-recourse investment, therefore the carrying value is zero. (d) Represents a variable interest entity. (e) The Company is entitled to a 15% return on its cumulative capital contribution which was $15.7 million and $15.4 million at March 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 $30.2 million and $36.8 million at March 31, 2018 and December 31, 2017 , respectively. (f) Represents deferred fees. (g) Includes a cost-method investment in Albertson’s ( Note 8 ) and other investments. (h) Distributions have exceeded the Company’s investment; however, the Company recognizes a liability balance as it may be required to fund future obligations of the entity.
Schedule of Condensed Balance Sheet	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): March 31, December 31, 2018 2017 Combined and Condensed Balance Sheets Assets: Rental property, net $ 509,634 $ 518,900 Real estate under development 24,976 26,681 Investment in unconsolidated affiliates 6,853 6,853 Other assets 95,934 100,901 Total assets $ 637,397 $ 653,335 Liabilities and partners’ equity: Mortgage notes payable $ 405,955 $ 405,652 Other liabilities 60,950 61,932 Partners’ equity 170,492 185,751 Total liabilities and partners’ equity $ 637,397 $ 653,335 Company's share of accumulated equity $ 183,602 $ 185,533 Basis differential 107,347 95,358 Deferred fees, net of portion related to the Company's interest 3,111 3,472 Amounts receivable by the Company 2,254 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 296,314 286,778 Company's share of distributions in excess of income from and investments in unconsolidated affiliates 15,226 15,292 Investments in and advances to unconsolidated affiliates $ 311,540 $ 302,070
Schedule of Condensed Income Statement	Three Months Ended March 31, 2018 2017 Combined and Condensed Statements of Income Total revenues $ 20,156 $ 21,603 Operating and other expenses (5,921 ) (5,866 ) Interest expense (4,874 ) (4,538 ) Depreciation and amortization (6,055 ) (6,449 ) Loss on debt extinguishment — (151 ) (Loss) gain on disposition of properties (418 ) 14,446 Net income attributable to unconsolidated affiliates $ 2,888 $ 19,045 Company’s share of equity in $ 2,267 $ 13,569 Basis differential amortization (583 ) (866 ) Company’s equity in earnings of unconsolidated affiliates $ 1,684 $ 12,703

Other Assets, Net and Account31

Other Assets, Net and Accounts Payable and Other Liabilities (Tables)	3 Months Ended
	Mar. 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: March 31, December 31, (in thousands) 2018 2017 Other Assets, Net: Lease intangibles, net ( Note 6 ) $ 125,050 $ 127,571 Deferred charges, net (a) 27,730 24,589 Prepaid expenses 17,927 16,838 Other receivables 5,719 11,356 Accrued interest receivable 12,450 11,668 Deposits 4,549 6,296 Due from seller 4,300 4,300 Deferred tax assets 2,141 2,096 Derivative financial instruments ( Note 8 ) 9,958 4,402 Due from related parties 2,397 1,479 Corporate assets 2,287 2,369 Income taxes receivable 2,006 1,995 $ 216,514 $ 214,959 (a) Deferred Charges, Net: Deferred leasing and other costs $ 41,985 $ 41,020 Deferred financing costs 8,634 7,786 50,619 48,806 Accumulated amortization (22,889 ) (24,217 ) Deferred charges, net $ 27,730 $ 24,589 Accounts Payable and Other Liabilities: Lease intangibles, net ( Note 6 ) $ 104,273 $ 104,478 Accounts payable and accrued expenses 59,771 61,420 Deferred income 31,260 31,306 Tenant security deposits, escrow and other 10,412 10,029 Derivative financial instruments ( Note 8 ) 1,238 1,467 Income taxes payable 575 176 Other 1,561 1,176 $ 209,090 $ 210,052

Lease Intangibles (Tables)

Lease Intangibles (Tables)	3 Months Ended
	Mar. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Finite-Lived Intangible Assets	Intangible assets and liabilities are summarized as follows (in thousands): March 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 $ 199,740 $ (81,262 ) $ 118,478 $ 193,821 $ (72,749 ) $ 121,072 Above-market rent 17,366 (10,794 ) 6,572 16,786 (10,287 ) 6,499 $ 217,106 $ (92,056 ) $ 125,050 $ 210,607 $ (83,036 ) $ 127,571 Amortizable Intangible Liabilities Below-market rent $ (150,211 ) $ 46,560 $ (103,651 ) $ (147,232 ) $ 43,391 $ (103,841 ) Above-market ground lease (671 ) 49 (622 ) (671 ) 34 (637 ) $ (150,882 ) $ 46,609 $ (104,273 ) $ (147,903 ) $ 43,425 $ (104,478 )
Schedule of Amortization of Acquired Lease Intangible Assets and Liabilities	The scheduled amortization of acquired lease intangible assets and assumed liabilities as of March 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) 2018 (Remainder) $ 6,219 $ (19,544 ) $ 44 $ (13,281 ) 2019 9,596 (23,316 ) 58 (13,662 ) 2020 8,830 (17,389 ) 58 (8,501 ) 2021 7,650 (12,760 ) 58 (5,052 ) 2022 7,353 (8,949 ) 58 (1,538 ) Thereafter 57,431 (36,520 ) 346 21,257 Total $ 97,079 $ (118,478 ) $ 622 $ (20,777 )

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
Schedule of Debt	A summary of the Company’s consolidated indebtedness is as follows (dollars in thousands): Interest Rate at March 31, December 31, Maturity Date at March 31, December 31, 2018 2017 March 31, 2018 2018 2017 Mortgages Payable Core Fixed Rate 3.88%-6.00% 3.88%-5.89% February 2024 - April 2035 $ 179,475 $ 179,870 Core Variable Rate - Swapped (a) 3.41%-3.77% 1.71%-3.77% January 2023 - June 2026 33,323 74,152 Total Core Mortgages Payable 212,798 254,022 Fund II Fixed Rate 1.00%-4.75% 1.00%-4.75% August 2019 - August 2042 205,262 205,262 Fund II Variable Rate - Swapped (a) 2.88% 2.88% November 2021 19,503 19,560 Total Fund II Mortgages Payable 224,765 224,822 Fund III Variable Rate Prime+0.50%-LIBOR+4.65% Prime+0.50%-LIBOR+4.65% May 2018 - December 2021 70,344 65,866 Fund IV Fixed Rate 3.40%-4.50% 3.40%-4.50% October 2025-June 2026 10,503 10,503 Fund IV Variable Rate LIBOR+1.70%-LIBOR+3.95% LIBOR+1.70%-LIBOR+3.95% April 2018 - August 2021 249,954 250,584 Fund IV Variable Rate - Swapped (a) 3.67%-4.23% 1.78%-2.11% May 2019 - December 2022 86,517 86,851 Total Fund IV Mortgages Payable 346,974 347,938 Fund V Variable Rate LIBOR+2.15%-LIBOR+2.25% LIBOR+2.25% October 2020 - January 2021 51,506 28,613 Fund V Variable Rate - Swapped (a) 4.61% — February 2021 16,900 — Total Fund V Mortgage Payable 68,406 28,613 Net unamortized debt issuance costs (12,590 ) (12,943 ) Unamortized premium 830 856 Total Mortgages Payable $ 911,527 $ 909,174 Unsecured Notes Payable Core Variable Rate Unsecured (a) 2.49%-4.05% 1.24%-3.77% March 2023 $ 350,000 $ 300,000 Fund II Unsecured Notes Payable LIBOR+1.65% LIBOR+1.40% September 2020 31,500 31,500 Fund IV Term Loan/Subscription Facility LIBOR+1.65%-LIBOR+2.75% LIBOR+1.65%-LIBOR+2.75% December 2018- October 2019 40,825 40,825 Fund V Subscription Facility LIBOR+1.60% LIBOR+1.60% May 2020 108,100 103,300 Net unamortized debt issuance costs (669 ) (1,890 ) Total Unsecured Notes Payable $ 529,756 $ 473,735 Unsecured Line of Credit Core Unsecured Line of Credit — LIBOR+1.40% — $ — $ 18,048 Core Unsecured Line of Credit - Swapped (a) 2.59%-4.15% 1.24%-3.77% March 2022 14,000 23,452 Total Unsecured Line of Credit $ 14,000 $ 41,500 Total Debt - Fixed Rate (b) $ 915,483 $ 899,650 Total Debt - Variable Rate (c) 552,229 538,736 Total Debt 1,467,712 1,438,386 Net unamortized debt issuance costs (13,259 ) (14,833 ) Unamortized premium 830 856 Total Indebtedness $ 1,455,283 $ 1,424,409 __________ (a) At March 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; PRIME + 0.50% to LIBOR + 4.65% for Fund III variable-rate debt; LIBOR + 1.85% to LIBOR + 2.25% for Fund IV variable-rate debt, LIBOR + 2.20% for Fund V and LIBOR + 1.25% for Core variable-rate unsecured term loans. (b) Includes $520.2 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.
Schedule of Maturities of Long-term Debt	The scheduled principal repayments of the Company’s consolidated indebtedness, as of March 31, 2018 are as follows (in thousands): Year Ending December 31, 2018 (Remainder) $ 52,396 2019 207,952 2020 494,608 2021 113,012 2022 62,529 Thereafter 537,215 1,467,712 Unamortized fair market value of assumed debt 830 Net unamortized debt issuance costs (13,259 ) Total indebtedness $ 1,455,283

Financial Instruments and Fai34

Financial Instruments and Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Schedule of fair value, assets and liabilities measured on recurring basis	The following table presents the Company’s fair value hierarchy for those assets and liabilities measured at fair value on a recurring basis (in thousands): March 31, 2018 December 31, 2017 Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Assets Money Market Funds $ 105 $ — $ — $ 3 $ — $ — Derivative financial instruments — 9,958 — — 4,402 — Liabilities Derivative financial instruments — 1,238 — — 1,467 —
Schedule of derivative financial instruments	The Company had the following interest rate swaps for the periods presented (dollars in thousands): Aggregate Strike Rate Balance Sheet Location Fair Value Derivative Instrument Effective Date Maturity Date Low High March 31, 2018 December 31, 2017 Core Interest Rate Swaps $ 69,864 October 2011 - March 2018 July 2018 - March 2028 2.9% — 3.77% Other Liabilities $ (1,238 ) $ (1,438 ) Interest Rate Swaps 336,823 February 2013 - December 2017 November 2018 - July 2027 1.24% — 3.77% Other Assets 8,458 4,076 $ 406,687 $ 7,220 $ 2,638 Fund II Interest Rate Swap $ 19,503 October 2014 November 2021 2.88% — 2.88% Other Assets $ 155 $ — Interest Rate Swaps — October 2014 November 2021 2.88% — 2.88% Other Liabilities — (29 ) Interest Rate Cap 29,500 April 2013 April 2018 4.00% — 4.00% Other Assets — — $ 49,003 $ 155 $ (29 ) Fund III Interest Rate Cap $ 58,000 December 2016 January 2020 3.00% — 3.00% Other Assets $ 48 $ 14 Fund IV Interest Rate Swaps $ 86,517 May 2014 - November 2017 May 2019 - April 2022 1.78% — 2.11% Other Assets $ 1,222 $ 295 Interest Rate Caps 108,900 July 2016 - November 2016 August 2019 - December 2019 3.00% — 3.00% Other Assets 65 17 $ 195,417 $ 1,287 $ 312 Fund V Interest Rate Swaps $ 16,900 January 2018 February 2021 2.41% — 2.41% Other Assets $ 10 $ — Total asset derivatives $ 9,958 $ 4,402 Total liability derivatives $ (1,238 ) $ (1,467 )
Gain (loss) on derivative instruments within the statement of income	The following table presents the location in the financial statements of the income (losses) recognized related to the Company’s cash flow hedges (in thousands): Three Months Ended March 31, 2018 2017 Amount of (loss) income related to the effective portion recognized in other comprehensive income $ 5,653 $ 118 Amount of loss related to the effective portion subsequently reclassified to earnings — — Amount of gain (loss) related to the ineffective portion and amount excluded from effectiveness testing — —
Fair value, by balance sheet grouping	The Company’s other financial instruments had the following carrying values and fair values as of the dates shown (dollars in thousands): March 31, 2018 December 31, 2017 Level Carrying Estimated Carrying Estimated Notes Receivable (a) 3 $ 108,959 $ 105,985 $ 153,829 $ 151,712 Mortgage and Other Notes Payable (a) 3 923,287 912,968 921,261 921,891 Investment in non-traded equity securities (b) 3 — 22,824 — 22,824 Unsecured notes payable and Unsecured line of credit (c) 2 544,425 544,506 517,125 515,330 __________ (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.

Shareholders' Equity, Noncont35

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income (Tables)	3 Months Ended
	Mar. 31, 2018
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]
Reclassification out of Accumulated Other Comprehensive Income	The following table sets forth the activity in accumulated other comprehensive income for the three months ended March 31, 2018 and 2017 (in thousands): Gains or Losses on Derivative Instruments Balance at January 1, 2018 $ 2,614 Other comprehensive income before reclassifications 5,653 Reclassification of realized interest on swap agreements 363 Net current period other comprehensive income 6,016 Net current period other comprehensive income attributable to noncontrolling interests (1,254 ) Balance at March 31, 2018 $ 7,376 Balance at January 1, 2017 $ (798 ) Other comprehensive income before reclassifications 118 Reclassification of realized interest on swap agreements 963 Net current period other comprehensive income 1,081 Net current period other comprehensive loss attributable to noncontrolling interests 155 Balance at March 31, 2017 $ 438
Change in Noncontrolling Interests	The following table summarizes the change in the noncontrolling interests for the three months ended March 31, 2018 and 2017 (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 $0.27 per Common OP Unit (1,721 ) — (1,721 ) Net income (loss) for the period January 1 through March 31, 2018 612 (12,191 ) (11,579 ) Conversion of 36,126 Common OP Units to (642 ) — (642 ) Other comprehensive income - unrealized loss 274 886 1,160 Reclassification of realized interest expense on swap agreements 10 84 94 Noncontrolling interest distributions — (695 ) (695 ) Employee Long-term Incentive Plan Unit Awards 3,716 — 3,716 Rebalancing adjustment (c) 1,225 — 1,225 Balance at March 31, 2018 $ 106,395 $ 533,603 $ 639,998 Balance at January 1, 2017 $ 95,422 $ 494,126 $ 589,548 Distributions declared of $0.26 per Common OP Unit (1,617 ) — (1,617 ) Net income for the period January 1 through March 31, 2017 1,062 3,278 4,340 Conversion of 24,860 Common OP Units to Common Shares (438 ) — (438 ) Other comprehensive income - unrealized loss 21 (317 ) (296 ) Reclassification of realized interest expense on swap agreements 49 92 141 Noncontrolling interest contributions — 20,269 20,269 Noncontrolling interest distributions — (3,822 ) (3,822 ) Employee Long-term Incentive Plan Unit Awards 4,141 — 4,141 Rebalancing adjustment (c) 5,693 — 5,693 Balance at March 31, 2017 $ 104,333 $ 513,626 $ 617,959 __________ (a) Noncontrolling interests in the Operating Partnership are comprised of (i) the limited partners’ 3,328,873 Common OP Units at March 31, 2018 and December 31, 2017 ; (ii) 188 Series A Preferred OP Units at March 31, 2018 and December 31, 2017 ; (iii) 136,593 Series C Preferred OP Units at March 31, 2018 and December 31, 2017 ; and (iv) 2,619,872 and 2,274,147 LTIP units as of at March 31, 2018 and December 31, 2017 , respectively, as discussed in Share Incentive Plan ( Note 13 ). Distributions declared for Preferred OP Units are reflected in net income in the table above. (b) Noncontrolling interests in partially-owned affiliates comprise third-party interests in Funds II, III, IV and V, and Mervyns I and II, and six other subsidiaries. (c) 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)

Leases (Tables)	3 Months Ended
	Mar. 31, 2018
Leases [Abstract]
Schedule of Future Minimum Rental Payments for Operating Leases	The scheduled future minimum (i) rental revenues from rental properties under the terms of all non-cancelable tenant leases, assuming no new or renegotiated leases or option extensions for such premises and (ii) rental payments under the terms of all non-cancelable operating and capital leases in which the Company is the lessee, principally for office space and ground leases, as of March 31, 2018 , are summarized as follows (in thousands): Year Ending December 31, Minimum Rental Revenues Minimum Rental Payments 2018 (Remainder) $ 125,069 $ 4,546 2019 169,873 4,565 2020 155,238 4,256 2021 135,874 4,364 2022 116,972 4,400 Thereafter 527,122 183,911 Total $ 1,230,148 $ 206,042

Segment Reporting (Tables)

Segment Reporting (Tables)	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Reconciliation of Certain Segment Information from Segments to Consolidated	The following tables set forth certain segment information for the Company (in thousands): As of or for the Three Months Ended March 31, 2018 Core Portfolio Funds Structured Financing Unallocated Total Revenues $ 41,628 $ 21,496 $ — $ — $ 63,124 Depreciation and amortization (15,498 ) (13,078 ) — — (28,576 ) Property operating expenses, other operating and real estate taxes (10,894 ) (8,483 ) — — (19,377 ) General and administrative expenses — — — (8,470 ) (8,470 ) Operating income (loss) 15,236 (65 ) — (8,470 ) 6,701 Interest income — — 3,737 — 3,737 Equity in earnings of unconsolidated affiliates inclusive of gains on disposition of properties 1,426 258 — — 1,684 Interest expense (6,502 ) (9,388 ) — — (15,890 ) Income tax provision — — — (392 ) (392 ) Net income (loss) 10,160 (9,195 ) 3,737 (8,862 ) (4,160 ) Net income (loss) attributable to noncontrolling interests (73 ) 11,652 — — 11,579 Net income attributable to Acadia $ 10,087 $ 2,457 $ 3,737 $ (8,862 ) $ 7,419 Real estate at cost $ 2,042,280 $ 1,487,525 $ — $ — $ 3,529,805 Total assets $ 2,283,451 $ 1,546,566 $ 108,959 $ — $ 3,938,976 Cash paid for acquisition of real estate $ 1,337 $ 44,834 $ — $ — $ 46,171 Cash paid for development and property improvement costs $ 5,946 $ 12,190 $ — $ — $ 18,136 As of or for the Three Months Ended March 31, 2017 Core Portfolio Funds Structured Financing Unallocated Total Revenues $ 44,446 $ 17,553 $ — $ — $ 61,999 Depreciation and amortization (16,439 ) (8,097 ) — — (24,536 ) Property operating expenses, other operating and real estate taxes (12,853 ) (6,244 ) — — (19,097 ) General and administrative expenses — — — (8,469 ) (8,469 ) Operating income 15,154 3,212 — (8,469 ) 9,897 Interest income — — 8,984 — 8,984 Equity in earnings of unconsolidated affiliates inclusive of gains on disposition of properties 560 12,143 — — 12,703 Interest expense (7,155 ) (4,333 ) — — (11,488 ) Income tax provision — — — (125 ) (125 ) Net income 8,559 11,022 8,984 (8,594 ) 19,971 Net income attributable to noncontrolling interests (432 ) (3,908 ) — — (4,340 ) Net income attributable to Acadia $ 8,127 $ 7,114 $ 8,984 $ (8,594 ) $ 15,631 Real estate at cost $ 1,983,365 $ 1,480,201 $ — $ — $ 3,463,566 Total assets $ 2,246,037 $ 1,498,045 $ 276,507 $ — $ 4,020,589 Cash paid for acquisition of real estate $ — $ 34,688 $ — $ — $ 34,688 Cash paid for development and property improvement costs $ 996 $ 26,019 $ — $ — $ 27,015

Share Incentive and Other Com38

Share Incentive and Other Compensation (Tables)	3 Months Ended
	Mar. 31, 2018
Disclosure of Compensation Related Costs, Share-based 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 Common Restricted Weighted LTIP Units Weighted Unvested at January 1, 2017 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 5,768 25.96 381,821 27.28 Vested (12,784 ) 31.21 (288,913 ) 30.34 Forfeited (47 ) 35.37 — — Unvested at March 31, 2018 34,264 $ 25.14 1,003,007 $ 27.30

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	Three Months Ended March 31, (dollars in thousands) 2018 2017 Numerator: Net income attributable to Acadia $ 7,419 $ 15,631 Less: net income attributable to participating securities (44 ) (162 ) Income from continuing operations net of income $ 7,375 $ 15,469 Denominator: Weighted average shares for basic earnings per share 83,434,083 83,634,727 Effect of dilutive securities: Employee unvested restricted shares 4,394 10,730 Denominator for diluted earnings per share 83,438,477 83,645,457 Basic and diluted earnings per Common Share from $ 0.09 $ 0.18 Anti-Dilutive Shares Excluded from Denominator: Series A Preferred OP Units 188 188 Series A Preferred OP Units - Common share equivalent 25,067 25,067 Series C Preferred OP Units 136,593 141,593 Series C Preferred OP Units - Common share equivalent 474,278 471,035

Organization, Basis of Presen40

Organization, Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2018USD ($)segmentproperty	Mar. 31, 2017USD ($)	Dec. 31, 2017USD ($)
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of reportable segments | segment	3
Net cash provided by (used in) investing activities	$ (26,279,000)	$ (39,303,000)
Net cash provided by (used in) operating activities	22,939,000	24,489,000
Capitalized acquisition costs	$ 100,000
Acquisition costs expensed		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		7,300,000
Net cash provided by (used in) operating activities		(7,300,000)
Accounting Standards Update 2016-18
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Net cash provided by (used in) operating activities		(1,000,000)
Increase (decrease) in cash and cash equivalents		1,000,000
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%		95.00%
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%
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		$ 200,000
Opportunity Funds
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of retail properties | property	57
Core Portfolio and Opportunity Funds
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of retail properties | property	175

Organization, Basis of Presen41

Organization, Basis of Presentation and Summary of Significant Accounting Policies - Schedule of Operating Partnership's Equity Interest (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)
Fund II and Mervyns II
Variable Interest Entity [Line Items]
Operating Partnership Share of Capital	28.33%
Capital called	$ 347.1
Unfunded Commitment	$ 0
Equity Interest Held By Operating Partnership	28.33%
Preferred Return	8.00%
Total distributions	$ 131.6
Fund III
Variable Interest Entity [Line Items]
Operating Partnership Share of Capital	24.54%
Capital called	$ 411.5
Unfunded Commitment	$ 38.5
Equity Interest Held By Operating Partnership	24.54%
Preferred Return	6.00%
Total distributions	$ 551.9
Fund IV
Variable Interest Entity [Line Items]
Operating Partnership Share of Capital	23.12%
Capital called	$ 412.7
Unfunded Commitment	$ 117.3
Equity Interest Held By Operating Partnership	23.12%
Preferred Return	6.00%
Total distributions	$ 131.5
Fund V
Variable Interest Entity [Line Items]
Operating Partnership Share of Capital	20.10%
Capital called	$ 45.8
Unfunded Commitment	$ 474.2
Equity Interest Held By Operating Partnership	20.10%
Preferred Return	6.00%
Total distributions	$ 0

Real Estate - Schedule of Real

Real Estate - Schedule of Real Estate (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Acquisition and Disposition of Properties and Discontinued Operations [Abstract]
Land	$ 667,847	$ 658,835
Buildings and improvements	2,444,871	2,406,488
Tenant improvements	136,682	131,850
Construction in progress	21,060	18,642
Properties under capital lease	76,965	76,965
Total	3,347,425	3,292,780
Less: Accumulated depreciation	(359,048)	(339,862)
Operating real estate, net	2,988,377	2,952,918
Real estate under development, at cost	182,380	173,702
Net investments in real estate	$ 3,170,757	$ 3,126,620

Real Estate - Acquisitions and

Real Estate - Acquisitions and Conversions (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Business Acquisition [Line Items]
Purchase Price	$ 46,596		$ 254,532
Debt assumed	0		0
Capitalized acquisition costs	100
Acquisition costs expensed		$ 300
Purchase Price Allocation
Land	9,012		48,138
Buildings and improvements	34,064		173,576
Other assets	0		84
Acquisition-related intangible assets (in Acquired lease intangibles, net)	6,499		44,269
Acquisition-related intangible liabilities (in Acquired lease intangibles, net)	(2,979)		(11,535)
Net assets acquired	46,596		254,532
Consideration
Cash	46,171		200,429
Conversion of note receivable	0		41,010
Liabilities assumed	425		3,363
Existing interest in previously unconsolidated investment	0		4,159
Change in control of previously unconsolidated investment	0		5,571
Total Consideration	46,596		254,532
Core Portfolio
Business Acquisition [Line Items]
Purchase Price	1,337		42,800
Debt assumed	$ 0		$ 0
Acquisition costs expensed		200
Core Portfolio | Bedford Green Land Parcel
Business Acquisition [Line Items]
Percent Acquired	100.00%
Purchase Price	$ 1,337
Debt assumed	0
Core Portfolio | Market Square Shopping Center | Wilmington, DE
Business Acquisition [Line Items]
Percent Acquired			100.00%
Purchase Price			$ 42,800
Debt assumed			0
Funds Segment
Business Acquisition [Line Items]
Capitalized acquisition costs	100
Acquisition costs expensed		$ 100
Fund IV
Business Acquisition [Line Items]
Purchase Price			44,492
Debt assumed			$ 0
Fund IV | Lincoln Place - Fairview Heights, IL | Fairview Heights, IL
Business Acquisition [Line Items]
Percent Acquired			100.00%
Purchase Price			$ 35,350
Debt assumed			$ 0
Fund IV | Shaw's Plaza Waterville, ME | Windham, ME
Business Acquisition [Line Items]
Percent Acquired			100.00%
Purchase Price			$ 9,142
Debt assumed			0
Fund V
Business Acquisition [Line Items]
Purchase Price	45,259		167,240
Debt assumed	$ 0		$ 0
Fund V | Trussville Promenade - Trussville, AL | Trussville, AL
Business Acquisition [Line Items]
Percent Acquired	100.00%
Purchase Price	$ 45,259
Debt assumed	$ 0
Fund V | Plaza Santa Fe - Santa Fe, NM | Santa Fe, NM
Business Acquisition [Line Items]
Percent Acquired			100.00%
Purchase Price			$ 35,220
Debt assumed			$ 0
Fund V | Hickory Ridge - Hickory, NC | Hickory, NC
Business Acquisition [Line Items]
Percent Acquired			100.00%
Purchase Price			$ 44,020
Debt assumed			$ 0
Fund V | New Towne Plaza - Canton, MI | Canton, MI
Business Acquisition [Line Items]
Percent Acquired			100.00%
Purchase Price			$ 26,000
Debt assumed			$ 0
Fund V | Fairlane Green | Allen Park, MI
Business Acquisition [Line Items]
Percent Acquired			100.00%
Purchase Price			$ 62,000
Debt assumed			$ 0

Real Estate - Dispositions (Det

Real Estate - Dispositions (Details) - Disposal Group, Not Discontinued Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Price	$ 281,338
Gain/(Loss) on Sale	48,886
STATEMENTS OF INCOME
Rental revenues		$ 2,840
Expenses		(4,803)
Loss from continuing operations of disposed properties before gain on disposition of properties		(1,963)
Net income attributable to noncontrolling interests		1,405
Net loss attributable to Acadia		$ (558)
Fund III | New Hyde Park Shopping Center
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Price	22,075
Gain/(Loss) on Sale	6,433
Fund II | 216th Street
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Price	30,579
Gain/(Loss) on Sale	6,543
Fund II | City Point Condominium Tower I
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Price	96,000
Gain/(Loss) on Sale	(810)
Fund II | 260 E 161th Street
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Price	105,684
Gain/(Loss) on Sale	31,537
Fund IV | 1151 Third Avenue
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Price	27,000
Gain/(Loss) on Sale	$ 5,183

Real Estate - Properties Held F

Real Estate - Properties Held For Sale (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)property	Mar. 31, 2017USD ($)	Dec. 31, 2017USD ($)property
Fund II
Long Lived Assets Held-for-sale [Line Items]
Number of properties held-for-sale | property	1		1
Properties held-for-sale	$ 25.4		$ 25.4
Disposal group, held-for-sale
Long Lived Assets Held-for-sale [Line Items]
Properties held for sale net loss	$ 0.1	$ 0.3

Real Estate - Real Estate Under

Real Estate - Real Estate Under Development and Construction in Progress (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018USD ($)property	Dec. 31, 2017USD ($)property
Property, Plant and Equipment [Line Items]
Number of properties under development | property	5	5
Real estate under development, beginning balance	$ 173,702
Transfers In	0
Capitalized Costs	8,678
Transfers Out	0
Real estate under development, ending balance	$ 182,380	$ 173,702
Number of unconsolidated project in development | property	1	1
Core Portfolio
Property, Plant and Equipment [Line Items]
Number of properties under development | property	2	2
Real estate under development, beginning balance	$ 21,897
Transfers In	0
Capitalized Costs	2,159
Transfers Out	0
Real estate under development, ending balance	$ 24,056	$ 21,897
Number of projects put into service during period | property		1
Fund Portfolio | Fund II
Property, Plant and Equipment [Line Items]
Number of properties under development | property	0	0
Real estate under development, beginning balance	$ 4,908
Transfers In	0
Capitalized Costs	(175)
Transfers Out	0
Real estate under development, ending balance	$ 4,733	$ 4,908
Fund Portfolio | Fund III
Property, Plant and Equipment [Line Items]
Number of properties under development | property	2	2
Real estate under development, beginning balance	$ 63,939
Transfers In	0
Capitalized Costs	6,431
Transfers Out	0
Real estate under development, ending balance	$ 70,370	$ 63,939
Fund Portfolio | Fund IV
Property, Plant and Equipment [Line Items]
Number of properties under development | property	1	1
Real estate under development, beginning balance	$ 82,958
Transfers In	0
Capitalized Costs	263
Transfers Out	0
Real estate under development, ending balance	$ 83,221	$ 82,958
Number of unconsolidated project in development | property		4
Number of projects put into service during period | property		3

Notes Receivable, Net - Schedul

Notes Receivable, Net - Schedule of Notes Receivable (Details) $ in Thousands	Mar. 31, 2018USD ($)debtinstrument	Dec. 31, 2017USD ($)
Mortgage Loans on Real Estate [Line Items]
Net carrying amount of notes receivable | $	$ 108,959	$ 153,829
Number of instruments held | debtinstrument	5
Core Portfolio
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
Mortgage Loans on Real Estate [Line Items]
Effective interest rate	6.00%
Core Portfolio | Maximum
Mortgage Loans on Real Estate [Line Items]
Effective interest rate	8.10%
Fund Portfolio | Fund II
Mortgage Loans on Real Estate [Line Items]
Net carrying amount of notes receivable | $	$ 31,978	31,778
Number of instruments held | debtinstrument	1
Effective interest rate	2.50%
Fund Portfolio | Fund III
Mortgage Loans on Real Estate [Line Items]
Net carrying amount of notes receivable | $	$ 5,256	5,106
Number of instruments held | debtinstrument	1
Effective interest rate	18.00%
Fund Portfolio | Fund IV
Mortgage Loans on Real Estate [Line Items]
Net carrying amount of notes receivable | $	$ 15,250	$ 15,250
Number of instruments held | debtinstrument	1
Effective interest rate	15.30%

Notes Receivable, Net - Narrati

Notes Receivable, Net - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Mortgage Loans on Real Estate [Line Items]
Proceeds from notes receivable	$ 26,000	$ 0
Recovered mortgage amount including accrued interest and fees			$ 16,800
Additional advance	47,273	$ 93,044
Notes receivable, net	108,959		153,829
Nonperforming Financial Instruments
Mortgage Loans on Real Estate [Line Items]
Proceeds from notes receivable			12,000
Core Portfolio
Mortgage Loans on Real Estate [Line Items]
Proceeds from notes receivable	26,000
Note receivable accrued interest	200
Notes receivable, net	56,475		101,695
Core Portfolio | Notes Receivable of $10 million
Mortgage Loans on Real Estate [Line Items]
Additional advance			10,000
Notes receivable, net			20,000
Core Portfolio | Note Receivable, Due June 1, 2018
Mortgage Loans on Real Estate [Line Items]
Notes receivable, net			15,000
Core Portfolio | Note Receivable Due April 1, 2020
Mortgage Loans on Real Estate [Line Items]
Additional advance	$ 2,800
Maximum | Core Portfolio
Mortgage Loans on Real Estate [Line Items]
Effective interest rate	8.10%
Town Center | Core Portfolio
Mortgage Loans on Real Estate [Line Items]
Note receivable exchanged	$ 22,000
Note receivable accrued interest	300
Shopping Center in Windham, ME
Mortgage Loans on Real Estate [Line Items]
Note receivable exchanged			9,000
Note receivable accrued interest			100
Fund III
Mortgage Loans on Real Estate [Line Items]
Additional advance	200		600
Fund II
Mortgage Loans on Real Estate [Line Items]
Note receivable accrued interest	$ 200		800
Market Square And Town Center Properties [Member] | Core Portfolio
Mortgage Loans on Real Estate [Line Items]
Note receivable exchanged			92,700
Note receivable accrued interest			$ 1,800

Investments in and Advances t49

Investments in and Advances to Unconsolidated Affiliates - Schedule of Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Due from related parties	$ 2,254	$ 2,415
Other	556	556
Investments in and advances to unconsolidated affiliates	311,540	302,070
Distributions in excess of income from, and investments in, unconsolidated affiliates	$ 15,226	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	$ 161	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	$ 367	373
Broughton St. Portfolio Savannah, GA
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	50.00%
Equity method investments	$ 41,331	48,335
Cumulative capital contribution, percentage	15.00%
Cumulative capital contribution	$ 15,700	15,400
Preferred return percentage	9.00%
Preferred return	$ 30,200	36,800
Fund IV Other Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	90.00%
Equity method investments	$ 16,101	20,199
650 Bald Hill Road
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	90.00%
Equity method investments	$ 13,506	13,609
Fund IV
Schedule of Equity Method Investments [Line Items]
Equity method investments	70,938	82,143
Core Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 237,425	216,583
Core Portfolio | 840 N. Michigan
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	88.43%
Equity method investments	$ 69,265	69,846
Core Portfolio | Renaissance Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	20.00%
Equity method investments	$ 34,294	35,041
Core Portfolio | Gotham Plaza
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	49.00%
Equity method investments	$ 29,408	29,416
Core Portfolio | Town Center
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	75.22%
Equity method investments	$ 100,918	78,801
Core Portfolio | Georgetown Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	50.00%
Equity method investments	$ 3,540	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	$ 15,226	$ 15,292

Investments in and Advances t50

Investments in and Advances to Unconsolidated Affiliates - Core Portfolio (Details) $ in Thousands	Mar. 28, 2018USD ($)	Nov. 16, 2017USD ($)	May 01, 2017USD ($)	Jan. 04, 2017USD ($)ft²	Apr. 29, 2016USD ($)	Mar. 31, 2018USD ($)ft²property	Dec. 31, 2017USD ($)
Schedule of Equity Method Investments [Line Items]
Purchase Price						$ 46,596	$ 254,532
Notes receivable, net						108,959	153,829
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 investments						$ 237,425	216,583
Core Portfolio | Crossroads
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage						49.00%
Core Portfolio | Georgetown Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage						50.00%
Equity method investments						$ 3,540	3,479
Core Portfolio | Gotham Plaza
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage						49.00%
Equity method investments						$ 29,408	29,416
Core Portfolio | Renaissance Portfolio
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage						20.00%
Square footage of real estate property (in square feet) | ft²						213,000
Percentage of voting interests acquired				20.00%
Number of businesses acquired | property						18
Equity method investments						$ 34,294	$ 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 | Town Center
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage		22.22%				75.22%	61.11%
Note receivable exchanged						$ 22,000
Note receivable accrued interest						$ 300
Equity method investment, ownership percentage by third party	14.11%	38.89%				24.78%
Equity method investments	$ 22,300	$ 61,600
Gain on equity method investment	$ 12,700	$ 34,500
Core Portfolio | Market Square
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage		22.22%	61.11%
Equity method investment, ownership percentage by third party		38.89%	38.89%
Equity method investments			$ 16,300
Gain on equity method investment			$ 9,800
Core Portfolio | Alexandria, Virginia | Renaissance Portfolio
Schedule of Equity Method Investments [Line Items]
Square footage of real estate property (in square feet) | ft²				6,200
Purchase Price				$ 3,000
Number of businesses acquired | property						2
Core Portfolio | Washington D.C. | Renaissance Portfolio
Schedule of Equity Method Investments [Line Items]
Number of businesses acquired | property						16
Exchange Transaction One | Core Portfolio | Brandywine Portfolio
Schedule of Equity Method Investments [Line Items]
Note receivable exchanged		$ 16,000
Note receivable accrued interest		600
Exchange Transaction Two | Core Portfolio | Brandywine Portfolio
Schedule of Equity Method Investments [Line Items]
Note receivable exchanged		60,700
Note receivable accrued interest		$ 900

Investments in and Advances t51

Investments in and Advances to Unconsolidated Affiliates - Fund Investments (Details)	Jan. 18, 2018USD ($)property	Jun. 30, 2017USD ($)	Feb. 15, 2017USD ($)	Jan. 31, 2017USD ($)	Mar. 31, 2018USD ($)property	Dec. 21, 2017USD ($)property	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2017USD ($)
Schedule of Equity Method Investments [Line Items]
Cost method investments					$ 556,000				$ 556,000
Equity in earnings (losses) of unconsolidated affiliates					1,684,000			$ 12,703,000
Mervyns I and Mervyns II
Schedule of Equity Method Investments [Line Items]
Distribution from equity method investment					1,100,000
Equity method investments					0
Albertson's
Schedule of Equity Method Investments [Line Items]
Distribution from cost method investment					2,400,000
Cost method investments					0
Equity in earnings (losses) of unconsolidated affiliates					2,000,000
Fund IV
Schedule of Equity Method Investments [Line Items]
Equity method investments					70,938,000				82,143,000
Fund III
Schedule of Equity Method Investments [Line Items]
Equity method investments					$ 367,000				$ 373,000
Broughton St. Portfolio Savannah, GA | Fund IV
Schedule of Equity Method Investments [Line Items]
Number of retail properties | property					16
Disposed of by sale
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal							$ 3,300,000
Disposed of by sale | Partnership Interest
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal							800,000
Disposed of by sale | 2819 Kennedy Boulevard | Fund IV
Schedule of Equity Method Investments [Line Items]
Consideration received				$ 19,000,000
Proceeds from sale of equity method investments				10,600,000
Gain (loss) on disposal				6,300,000
Disposed of by sale | 2819 Kennedy Boulevard | Fund IV | Mortgages
Schedule of Equity Method Investments [Line Items]
Repayments of debt				8,400,000
Disposed of by sale | 2819 Kennedy Boulevard | Affiliated Entity | Fund IV
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal				6,200,000
Disposed of by sale | 2819 Kennedy Boulevard | Partnership Interest | Fund IV
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal				$ 1,400,000
Disposed of by sale | Arundel Plaza | Fund III
Schedule of Equity Method Investments [Line Items]
Consideration received			$ 28,800,000
Proceeds from sale of equity method investments			18,800,000
Gain (loss) on disposal			8,200,000
Disposed of by sale | Arundel Plaza | Fund III | Mortgages
Schedule of Equity Method Investments [Line Items]
Repayments of debt			10,000,000
Disposed of by sale | Arundel Plaza | Affiliated Entity | Fund III
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal			5,300,000
Disposed of by sale | Arundel Plaza | Partnership Interest | Fund III
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal			$ 1,300,000
Disposed of by sale | 1701 Belmont Avenue | Fund IV
Schedule of Equity Method Investments [Line Items]
Consideration received		$ 5,600,000					$ 5,600,000
Proceeds from sale of equity method investments		2,700,000
Disposed of by sale | 1701 Belmont Avenue | Fund IV | Mortgages
Schedule of Equity Method Investments [Line Items]
Repayments of debt		2,900,000
Disposed of by sale | 1701 Belmont Avenue | Affiliated Entity | Fund IV
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal		$ 3,300,000
Disposed of by sale | Broughton St. Portfolio Savannah, GA | Fund IV
Schedule of Equity Method Investments [Line Items]
Proceeds from sale of equity method investments						$ 11,000,000
Gain (loss) on disposal	$ 400,000					$ 1,200,000
Number of retail properties | property	2					5
Proceeds from Sale of Real Estate Held-for-investment	$ 8,000,000
Disposed of by sale | Broughton St. Portfolio Savannah, GA | Affiliated Entity | Fund IV
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal						$ 600,000
Disposed of by sale | Broughton St. Portfolio Savannah, GA | Partnership Interest | Fund IV
Schedule of Equity Method Investments [Line Items]
Gain (loss) on disposal	$ 0					$ 100,000

Investments in and Advances t52

Investments in and Advances to Unconsolidated Affiliates - Unconsolidated Affiliates (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Combined and Condensed Balance Sheets
Real estate under development	$ 182,380		$ 173,702
Investments in and advances to unconsolidated affiliates	311,540		302,070
Other assets	216,514		214,959
Total assets	3,938,976		3,960,247
Total liabilities and equity	3,938,976		3,960,247
Investments in and advances to unconsolidated affiliates, net of Company's share of distributions in excess of income from and investments in unconsolidated affiliates	296,314		286,778
Company's share of distributions in excess of income from and investments in unconsolidated affiliates	15,226		15,292
Investments in and advances to unconsolidated affiliates	311,540		302,070
Combined and Condensed Statements of Income
Total revenues	63,124	$ 61,999
Operating and other expenses	(56,423)	(52,102)
Depreciation and amortization	(28,576)	(24,536)
Company’s equity in earnings of unconsolidated affiliates	1,684	12,703
Equity Method Investee
Schedule of Equity Method Investments [Line Items]
Related party revenue	300	400
Expenses, related party	500	500
Unconsolidated Affiliates
Combined and Condensed Balance Sheets
Rental property, net	509,634		518,900
Real estate under development	24,976		26,681
Investments in and advances to unconsolidated affiliates	6,853		6,853
Other assets	95,934		100,901
Total assets	637,397		653,335
Mortgage notes payable	405,955		405,652
Other liabilities	60,950		61,932
Partners’ equity	170,492		185,751
Total liabilities and equity	637,397		653,335
Company's share of accumulated equity	183,602		185,533
Basis differential	107,347		95,358
Deferred fees, net of portion related to the Company's interest	3,111		3,472
Amounts receivable by the Company	2,254		2,415
Investments in and advances to unconsolidated affiliates	6,853		$ 6,853
Combined and Condensed Statements of Income
Total revenues	20,156	21,603
Operating and other expenses	(5,921)	(5,866)
Interest expense	(4,874)	(4,538)
Depreciation and amortization	(6,055)	(6,449)
Loss on debt extinguishment	0	(151)
(Loss) gain on disposition of properties	(418)	14,446
Net income attributable to unconsolidated affiliates	2,888	19,045
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	2,267	13,569
Basis differential amortization	(583)	(866)
Company’s equity in earnings of unconsolidated affiliates	$ 1,684	$ 12,703

Other Assets, Net and Account53

Other Assets, Net and Accounts Payable and Other Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Other Assets, Net:
Lease intangibles, net (Note 6)	$ 125,050	$ 127,571
Deferred charges, net	27,730	24,589
Prepaid expenses	17,927	16,838
Other receivables	5,719	11,356
Accrued interest receivable	12,450	11,668
Deposits	4,549	6,296
Due from seller	4,300	4,300
Deferred tax assets	2,141	2,096
Derivative financial instruments (Note 8)	9,958	4,402
Due from related parties	2,397	1,479
Corporate assets	2,287	2,369
Income taxes receivable	2,006	1,995
Other assets, net	216,514	214,959
Deferred Charges, Net:
Deferred leasing and other costs	41,985	41,020
Deferred financing costs	8,634	7,786
Deferred costs, gross	50,619	48,806
Accumulated amortization	(22,889)	(24,217)
Deferred charges, net	27,730	24,589
Accounts Payable and Other Liabilities:
Lease intangibles, net (Note 6)	104,273	104,478
Accounts payable and accrued expenses	59,771	61,420
Deferred income	31,260	31,306
Tenant security deposits, escrow and other	10,412	10,029
Derivative financial instruments (Note 8)	1,238	1,467
Income taxes payable	575	176
Other	1,561	1,176
Accounts payable and other liabilities	$ 209,090	$ 210,052

Lease Intangibles - Schedule of

Lease Intangibles - Schedule of Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Amortizable Intangible Assets, Gross Carrying Amount	$ 217,106	$ 210,607
Amortizable Intangible Assets, Accumulated Amortization	(92,056)	(83,036)
Amortizable Intangible Assets, Net Carrying Amount	125,050	127,571
Amortizable Intangible Liabilities
Amortizable Intangible Liabilities, Gross Carrying Amount	(150,211)	(147,232)
Amortizable Intangible Liabilities, Accumulated Amortization	46,560	43,391
Amortizable Intangible Liabilities, Net Carrying Amount	(103,651)	(103,841)
Above-market Ground Lease, Gross	(671)	(671)
Above-market Ground Lease, Accumulated Amortization	49	34
Above-market Ground Lease, Net	(622)	(637)
Finite-Lived Intangible Liabilities, Gross	(150,882)	(147,903)
Finite-Lived Intangible Liabilities, Accumulated Amortization	46,609	43,425
Finite-Lived Intangible Liabilities, Net	(104,273)	(104,478)
Below market rents, acquired	$ 3,000	$ 10,900
Below market rents acquired, weighted average useful life	25 years 8 months	12 years 1 month
Above-market ground lease, acquired		$ 700
Above-market ground lease acquired, weighted average useful life		11 years 6 months
In-place lease intangible assets
Finite-Lived Intangible Assets [Line Items]
Amortizable Intangible Assets, Gross Carrying Amount	$ 199,740	$ 193,821
Amortizable Intangible Assets, Accumulated Amortization	(81,262)	(72,749)
Amortizable Intangible Assets, Net Carrying Amount	118,478	121,072
Intangible assets acquired	$ 5,900	$ 41,600
Acquired intangible assets, weighted average useful life	4 years 7 months	4 years 1 month
Above-market rent
Finite-Lived Intangible Assets [Line Items]
Amortizable Intangible Assets, Gross Carrying Amount	$ 17,366	$ 16,786
Amortizable Intangible Assets, Accumulated Amortization	(10,794)	(10,287)
Amortizable Intangible Assets, Net Carrying Amount	6,572	6,499
Intangible assets acquired	$ 600	$ 2,700
Acquired intangible assets, weighted average useful life	1 year 1 month	4 years 9 months

Lease Intangibles - Scheduled A

Lease Intangibles - Scheduled Amortization (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Acquired Lease Intangibles [Abstract]
Amortizable Intangible Assets, Net Carrying Amount	$ (125,050)	$ (127,571)
In-place lease intangible assets
Acquired Lease Intangibles [Abstract]
2018 (Remainder), Net Increase In Lease Revenues	6,219
2019, Net Increase In Lease Revenues	9,596
2020, Net Increase In Lease Revenues	8,830
2021, Net Increase In Lease Revenues	7,650
2022, Net Increase In Lease Revenues	7,353
Thereafter, Net Increase In Lease Revenues	57,431
Net Increase In Lease Revenues, Total	97,079
2018 (Remainder), Increase to Amortization	(19,544)
2019, Increase to Amortization	(23,316)
2020, Increase to Amortization	(17,389)
2021, Increase to Amortization	(12,760)
2022, Increase to Amortization	(8,949)
Thereafter, Increase to Amortization	(36,520)
Amortizable Intangible Assets, Net Carrying Amount	(118,478)	$ (121,072)
2018 (Remainder), Reduction of Rent Expense	44
2019, Reduction of Rent Expense	58
2020, Reduction of Rent Expense	58
2021, Reduction of Rent Expense	58
2022, Reduction of Rent Expense	58
Thereafter, Reduction of Rent Expense	346
Reduction of Rent Expense, Total	622
2018 (Remainder), Net Income (Expense)	(13,281)
2019, Net Income (Expense)	(13,662)
2020, Net Income (Expense)	(8,501)
2021, Net Income (Expense)	(5,052)
2022, Net Income (Expense)	(1,538)
Thereafter, Net Income (Expense)	21,257
Total, Net Income (Expense)	$ (20,777)

Debt - Summary of Consolidated

Debt - Summary of Consolidated Indebtedness (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term debt, gross	$ 1,467,712	$ 1,438,386
Mortgage and other notes payable, net	911,527	909,174
Unsecured notes payable, net	529,756	473,735
Unsecured line of credit	14,000	41,500
Net unamortized debt issuance costs	(13,259)	(14,833)
Unamortized fair market value of assumed debt	830	856
Total indebtedness	1,455,283	1,424,409
Letters of credit, outstanding amount	19,700	19,700
Total Debt - Fixed and Effectively Fixed Rate
Debt Instrument [Line Items]
Long-term debt, gross	915,483	899,650
Total Debt - Variable Rate
Debt Instrument [Line Items]
Long-term debt, gross	552,229	538,736
Total Debt - Variable Rate Fixed and Effectively Fixed Rate During Period
Debt Instrument [Line Items]
Long-term debt, gross	520,200	504,000
Variable-rate debt that subject to interest cap agreements
Debt Instrument [Line Items]
Long-term debt, gross	143,800	141,100
Mortgages
Debt Instrument [Line Items]
Mortgage and other notes payable, net	911,527	909,174
Net unamortized debt issuance costs	(12,590)	(12,943)
Unamortized fair market value of assumed debt	830	856
Unsecured Debt
Debt Instrument [Line Items]
Unsecured notes payable, net	529,756	473,735
Net unamortized debt issuance costs	(669)	(1,890)
Line of Credit
Debt Instrument [Line Items]
Unsecured line of credit	$ 14,000	41,500
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 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	$ 212,798	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	$ 179,475	$ 179,870
Core Portfolio | Mortgages | Fixed Rate | Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	3.88%	3.88%
Core Portfolio | Mortgages | Fixed Rate | Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	6.00%	5.89%
Core Portfolio | Mortgages | Variable Rate - Swapped
Debt Instrument [Line Items]
Long-term debt, gross	$ 33,323	$ 74,152
Core Portfolio | Mortgages | Variable Rate - Swapped | Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	3.41%	1.71%
Core Portfolio | Mortgages | Variable Rate - Swapped | Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	3.77%	3.77%
Core Portfolio | Unsecured Debt | Variable Rate Unsecured Term Loans - Swapped
Debt Instrument [Line Items]
Long-term debt, gross	$ 350,000	$ 300,000
Core Portfolio | Unsecured Debt | Variable Rate Unsecured Term Loans - Swapped | Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	2.49%	1.24%
Core Portfolio | Unsecured Debt | Variable Rate Unsecured Term Loans - Swapped | Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	4.05%	3.77%
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		1.40%
Core Portfolio | Line of Credit | Unsecured Line of Credit - Swapped
Debt Instrument [Line Items]
Long-term debt, gross	$ 14,000	$ 23,452
Core Portfolio | Line of Credit | Unsecured Line of Credit - Swapped | LIBOR | Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	2.59%	1.24%
Core Portfolio | Line of Credit | Unsecured Line of Credit - Swapped | LIBOR | Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	4.15%	3.77%
Fund Portfolio | Mortgages | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.17%
Fund II | Fund Portfolio | Variable Rate Debt | LIBOR | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.39%
Fund II | Fund Portfolio | Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	$ 224,765	$ 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%
Fund II | Fund Portfolio | Mortgages | Fixed Rate | Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	4.75%	4.75%
Fund II | Fund Portfolio | Mortgages | Variable Rate - Swapped
Debt Instrument [Line Items]
Interest rate, stated percentage	2.88%	2.88%
Long-term debt, gross	$ 19,503	$ 19,560
Fund II | Fund Portfolio | Unsecured Debt | Unsecured Notes Payable
Debt Instrument [Line Items]
Long-term debt, gross	$ 31,500	$ 31,500
Fund II | Fund Portfolio | Unsecured Debt | Unsecured Notes Payable | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.65%	1.40%
Fund III | Fund Portfolio | Variable Rate Debt | LIBOR | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	4.65%
Fund III | Fund Portfolio | Variable Rate Debt | Prime Rate | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Fund III | Fund Portfolio | Mortgages | Variable Rate Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 70,344	$ 65,866
Fund III | Fund Portfolio | Mortgages | Variable Rate Debt | LIBOR | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	4.65%	4.65%
Fund III | Fund Portfolio | Mortgages | Variable Rate Debt | Prime Rate | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%	0.50%
Fund IV | Fund Portfolio | Variable Rate Debt | LIBOR | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.85%
Fund IV | Fund Portfolio | Variable Rate Debt | LIBOR | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Fund IV | Fund Portfolio | Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	$ 346,974	$ 347,938
Fund IV | Fund Portfolio | Mortgages | Fixed Rate
Debt Instrument [Line Items]
Long-term debt, gross	$ 10,503	$ 10,503
Fund IV | Fund Portfolio | Mortgages | Fixed Rate | Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage	3.40%	3.40%
Fund IV | Fund Portfolio | Mortgages | Fixed Rate | Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage	4.50%	4.50%
Fund IV | Fund Portfolio | Mortgages | Variable Rate - Swapped
Debt Instrument [Line Items]
Long-term debt, gross	$ 86,517	$ 86,851
Fund IV | Fund Portfolio | Mortgages | Variable Rate - Swapped | LIBOR | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	3.67%	1.78%
Fund IV | Fund Portfolio | Mortgages | Variable Rate - Swapped | LIBOR | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	4.23%	2.11%
Fund IV | Fund Portfolio | Mortgages | Variable Rate Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 249,954	$ 250,584
Fund IV | Fund Portfolio | Mortgages | Variable Rate Debt | LIBOR | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.70%	1.70%
Fund IV | Fund Portfolio | Mortgages | Variable Rate Debt | LIBOR | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	3.95%	3.95%
Fund IV | Fund Portfolio | Unsecured Debt | Term Loan / Subscription Facility
Debt Instrument [Line Items]
Long-term debt, gross	$ 40,825	$ 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%
Fund IV | Fund Portfolio | Unsecured Debt | Term Loan / Subscription Facility | LIBOR | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	2.75%	2.75%
Fund V | Fund Portfolio | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.20%
Fund V | Fund Portfolio | Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	$ 68,406	$ 28,613
Fund V | Fund Portfolio | Mortgages | Variable Rate - Swapped
Debt Instrument [Line Items]
Long-term debt, gross	$ 16,900	0
Fund V | Fund Portfolio | Mortgages | Variable Rate - Swapped | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	4.61%
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%
Fund V | Fund Portfolio | Mortgages | Variable Rate Debt | LIBOR | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Fund V | Fund Portfolio | Unsecured Debt | Subscription Line
Debt Instrument [Line Items]
Long-term debt, gross	$ 108,100	$ 103,300
Fund V | Fund Portfolio | Unsecured Debt | Subscription Line | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.60%	1.60%
Revolving Credit Facility | Core Portfolio | Unsecured Debt
Debt Instrument [Line Items]
Letters of credit, outstanding amount	$ 12,300	$ 12,300

Debt - Credit Facility (Details

Debt - Credit Facility (Details)	Feb. 20, 2018USD ($)
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 300,000,000
Unsecured Debt | Senior Unsecured Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	500,000,000
Unsecured Debt | Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	150,000,000
Unsecured Debt | $300 Million Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity	350,000,000
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
Core Portfolio | Unsecured Debt | $150 Million Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 150,000,000

Debt - Mortgage Payable (Detail

Debt - Mortgage Payable (Details)	3 Months Ended
	Mar. 31, 2018USD ($)propertyderivativeloan	Dec. 31, 2017property
Mortgages
Debt Instrument [Line Items]
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	1
Derivative, notional amount	$ 16,900,000
Derivative fixed interest rate	2.41%
Core Portfolio
Debt Instrument [Line Items]
Derivative, notional amount	$ 406,687,000
Core Portfolio | Mortgages
Debt Instrument [Line Items]
Number of notes repaid | loan	1
Repayments of debt	$ 40,400,000
Scheduled principal payment	$ 1,900,000
Fund Portfolio | Mortgages
Debt Instrument [Line Items]
Number of mortgage loans | loan	2
Borrowings, amount	$ 39,800,000
Brandywine Portfolio | Core Portfolio | Mortgages
Debt Instrument [Line Items]
Debt default, amount	$ 26,300,000
Interest rate, stated percentage	6.00%
Debt default interest	5.00%
Interest owner percentage in property	22.00%
Lawsuit damages sought, value	$ 32,900,000
LIBOR | Core Portfolio | Mortgages
Debt Instrument [Line Items]
Basis spread on variable rate	1.65%
LIBOR | Fund Portfolio | Mortgages
Debt Instrument [Line Items]
Basis spread on variable rate	2.17%

Debt - Unsecured Notes Payable

Debt - Unsecured Notes Payable (Details) - USD ($)	Feb. 20, 2018	Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 300,000,000
Long-term debt outstanding		$ 1,467,712,000	$ 1,438,386,000
Letters of credit, outstanding amount		19,700,000	19,700,000
Unsecured Notes Payable | Unsecured Debt
Debt Instrument [Line Items]
Debt available balance		65,500,000	70,300,000
Fund IV | Letter of Credit | Unsecured Debt
Debt Instrument [Line Items]
Letters of credit, outstanding amount		7,400,000	7,400,000
Fund IV | Bridge facility | Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity		41,812,000
Long-term line of credit, noncurrent		40,800,000	40,800,000
Remaining borrowing capacity		1,000,000	1,000,000
Fund IV | Subscription Line | Unsecured Debt
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
Fund V | Subscription Line | Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity		150,000,000
Long-term line of credit, noncurrent		108,100,000
Remaining borrowing capacity		41,900,000
Fund II | Term Loan Maturing In September 2020 | Secured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity		40,000,000
Long-term line of credit, noncurrent		31,500,000	31,500,000
Remaining borrowing capacity		8,500,000	8,500,000
Core Portfolio
Debt Instrument [Line Items]
Derivative, notional amount		406,687,000
Core Portfolio | $350 Million Term Loan | Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity	350,000,000
Long-term debt outstanding		350,000,000	300,000,000
Core Portfolio | $300 Million Term Loan | Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 300,000,000
Core Portfolio | LIBOR | $350 Million Term Loan | Unsecured Debt
Debt Instrument [Line Items]
Basis spread on variable rate	1.25%
Fund Portfolio | Fund IV
Debt Instrument [Line Items]
Derivative, notional amount		195,417,000
Fund Portfolio | Fund V | Subscription Line | Unsecured Debt
Debt Instrument [Line Items]
Long-term debt outstanding		108,100,000	103,300,000
Remaining borrowing capacity			46,700,000
Fund Portfolio | Fund II
Debt Instrument [Line Items]
Derivative, notional amount		49,003,000
Fund Portfolio | Fund II | Unsecured Notes Payable | Unsecured Debt
Debt Instrument [Line Items]
Long-term debt outstanding		$ 31,500,000	$ 31,500,000
Fund Portfolio | LIBOR | Fund V
Debt Instrument [Line Items]
Basis spread on variable rate		2.20%
Fund Portfolio | LIBOR | Fund V | Subscription Line | Unsecured Debt
Debt Instrument [Line Items]
Basis spread on variable rate		1.60%	1.60%
Fund Portfolio | LIBOR | Fund II | Unsecured Notes Payable | Unsecured Debt
Debt Instrument [Line Items]
Basis spread on variable rate		1.65%	1.40%
Interest Rate Swaps
Debt Instrument [Line Items]
Derivative, notional amount		$ 50,000,000
Derivative fixed interest rate		2.80%

Debt - Unsecured Revolving Line

Debt - Unsecured Revolving Lines of Credit (Details) - USD ($)	Mar. 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
Core Portfolio | Revolving Credit Facility | Unsecured Debt
Debt Instrument [Line Items]
Debt available balance	123,700,000		96,200,000
Maximum borrowing capacity	150,000,000
Credit facility amount outstanding	14,000,000		41,500,000
Letters of credit, outstanding amount	$ 12,300,000		$ 12,300,000

Debt - Scheduled Principal Repa

Debt - Scheduled Principal Repayments (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
2018 (Remainder)	$ 52,396
2,019	207,952
2,020	494,608
2,021	113,012
2,022	62,529
Thereafter	537,215
Long-term debt and convertible notes payable	1,467,712	$ 1,438,386
Unamortized fair market value of assumed debt	830	856
Net unamortized debt issuance costs	(13,259)	(14,833)
Total indebtedness	$ 1,455,283	$ 1,424,409

Financial Instruments and Fai62

Financial Instruments and Fair Value Measurements - Schedule of Assets and Liabilities on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Assets
Derivative financial instruments	$ 9,958	$ 4,402
Liabilities
Derivative financial instruments	1,238	1,467
Recurring | Level 1
Assets
Money Market Funds	105	3
Derivative financial instruments	0	0
Liabilities
Derivative financial instruments	0	0
Recurring | Level 2
Assets
Money Market Funds	0	0
Recurring | Level 3
Assets
Money Market Funds	0	0
Derivative financial instruments	0	0
Liabilities
Derivative financial instruments	$ 0	$ 0

Financial Instruments and Fai63

Financial Instruments and Fair Value Measurements - Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Fair value, liability derivatives	$ (1,238)	$ (1,467)
Fair value, asset derivatives	9,958	4,402
Interest Rate Swaps
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	50,000
Core Portfolio
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	406,687
Fair value, derivatives, net	7,220	2,638
Core Portfolio | Interest Rate Swaps | Other Liabilities
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	69,864
Fair value, liability derivatives	$ (1,238)	(1,438)
Core Portfolio | Interest Rate Swaps | Other Liabilities | Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	2.90%
Core Portfolio | Interest Rate Swaps | Other Liabilities | Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	3.77%
Core Portfolio | Interest Rate Swaps | Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 336,823
Fair value, asset derivatives	$ 8,458	4,076
Core Portfolio | Interest Rate Swaps | Other Assets | Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	1.24%
Core Portfolio | Interest Rate Swaps | Other Assets | Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	3.77%
Fund Portfolio | Fund II
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 49,003
Fair value, derivatives, net	155	(29)
Fund Portfolio | Fund II | Interest Rate Swaps | Other Liabilities
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	0
Fair value, liability derivatives	$ 0	(29)
Fund Portfolio | Fund II | Interest Rate Swaps | Other Liabilities | Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	2.88%
Fund Portfolio | Fund II | Interest Rate Swaps | Other Liabilities | Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	2.88%
Fund Portfolio | Fund II | Interest Rate Swaps | Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 19,503
Fair value, asset derivatives	$ 155	0
Fund Portfolio | Fund II | Interest Rate Swaps | Other Assets | Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	2.88%
Fund Portfolio | Fund II | Interest Rate Swaps | Other Assets | Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	2.88%
Fund Portfolio | Fund II | Interest Rate Cap | Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 29,500
Fair value, asset derivatives	$ 0	0
Fund Portfolio | Fund II | Interest Rate Cap | Other Assets | Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	4.00%
Fund Portfolio | Fund II | Interest Rate Cap | Other Assets | Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	4.00%
Fund Portfolio | Fund III | Interest Rate Cap | Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 58,000
Fair value, asset derivatives	$ 48	14
Fund Portfolio | Fund III | Interest Rate Cap | Other Assets | Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	3.00%
Fund Portfolio | Fund III | Interest Rate Cap | Other Assets | Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	3.00%
Fund Portfolio | Fund IV
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 195,417
Fair value, derivatives, net	1,287	312
Fund Portfolio | Fund IV | Interest Rate Swaps | Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	86,517
Fair value, asset derivatives	$ 1,222	295
Fund Portfolio | Fund IV | Interest Rate Swaps | Other Assets | Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	1.78%
Fund Portfolio | Fund IV | Interest Rate Swaps | Other Assets | Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	2.11%
Fund Portfolio | Fund IV | Interest Rate Cap | Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 108,900
Fair value, asset derivatives	$ 65	17
Fund Portfolio | Fund IV | Interest Rate Cap | Other Assets | Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	3.00%
Fund Portfolio | Fund IV | Interest Rate Cap | Other Assets | Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	3.00%
Fund Portfolio | Fund V | Interest Rate Swaps | Other Assets
Derivatives, Fair Value [Line Items]
Aggregate Notional Amount	$ 16,900
Fair value, asset derivatives	$ 10	$ 0
Fund Portfolio | Fund V | Interest Rate Swaps | Other Assets | Minimum
Derivatives, Fair Value [Line Items]
Strike Rate	2.41%
Fund Portfolio | Fund V | Interest Rate Swaps | Other Assets | Maximum
Derivatives, Fair Value [Line Items]
Strike Rate	2.41%

Financial Instruments and Fai64

Financial Instruments and Fair Value Measurements - Additional Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)
Fair Value Disclosures [Abstract]
Reclassification adjustment related to derivatives from AOCI to interest expense	$ (1.1)

Financial Instruments and Fai65

Financial Instruments and Fair Value Measurements - Gain (Loss) from Derivative Instruments (Details) - Cash Flow Hedging - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (loss) income related to the effective portion recognized in other comprehensive income	$ 5,653	$ 118
Amount of loss related to the effective portion subsequently reclassified to earnings	0	0
Amount of gain (loss) related to the ineffective portion and amount excluded from effectiveness testing	$ 0	$ 0

Financial Instruments and Fai66

Financial Instruments and Fair Value Measurements - Fair Value by Balance Sheet Grouping (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes Receivable	$ 108,959	$ 153,829
Mortgage and Other Notes Payable	1,455,283	1,424,409
Unsecured notes payable and Unsecured line of credit	529,756	473,735
Carrying Amount | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes Receivable	108,959	153,829
Mortgage and Other Notes Payable	923,287	921,261
Investment in non-traded equity securities	0	0
Carrying Amount | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unsecured notes payable and Unsecured line of credit	544,425	517,125
Estimated Fair Value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes Receivable	105,985	151,712
Mortgage and Other Notes Payable	912,968	921,891
Investment in non-traded equity securities	22,824	22,824
Estimated Fair Value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unsecured notes payable and Unsecured line of credit	$ 544,506	$ 515,330

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Contractual obligation	$ 87.1	$ 92.2
Letters of credit, outstanding amount	$ 19.7	$ 19.7

Shareholders' Equity, Noncont68

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Common Shares, Share Repurchases and Dividends and Distributions (Details) - USD ($)	Feb. 27, 2018	Nov. 08, 2017	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	May 10, 2017	May 09, 2017
Class of Stock [Line Items]
Common shares, authorized (in shares)			200,000,000		100,000,000	200,000,000	100,000,000
Authorized amount			$ 200,000,000
Number of shares repurchased during period (in shares)			1,304,194		0
Shares repurchased during period			$ 31,961,000
Remaining authorized repurchase amount			$ 168,000,000
Cash dividends declared per common share (in dollars per share)			$ 0.27	$ 0.26
Restricted Stock
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					$ 8,400,000
Regular Quarterly Cash Dividend
Class of Stock [Line Items]
Cash dividends declared, period increase (in dollars per share)		$ 0.01
Cash dividends declared per common share (in dollars per share)	$ 0.27	$ 0.27

Shareholders' Equity, Noncont69

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	$ 2,215,639	$ 2,178,125
Other comprehensive income before reclassifications	5,653	118
Reclassification of realized interest on swap agreements	363	963
Net current period other comprehensive loss	6,016	1,081
Ending Balance	2,164,667	2,196,493
AOCI Attributable to Parent
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	2,614	(798)
Ending Balance	7,376	438
AOCI Attributable to Noncontrolling Interest
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Net current period other comprehensive loss	$ (1,254)	$ 155

Shareholders' Equity, Noncont70

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Noncontrolling Interest (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	$ 648,440
Net income (loss)	(4,160)	$ 19,971
Conversion of Common OP Units to Common Shares by limited partners of the Operating Partnership	0	0
Other comprehensive income - unrealized loss on valuation of swap agreements	5,653	118
Reclassification of realized interest on swap agreements	363	963
Noncontrolling interest contributions		20,269
Noncontrolling interest distributions	(695)	(3,822)
Employee Long-term Incentive Plan Unit Awards	3,811	4,235
Rebalancing adjustment	0	$ 0
Ending Balance	$ 639,998
Distributions declared (in dollars per share)	$ 0.27	$ 0.26
Conversion of Common OP Units to Common Shares by limited partners of the Operating Partnership (in shares)	36,126		24,860
LTIP Units
Increase (Decrease) in Stockholders' Equity [Roll Forward]
LTIP units outstanding (in shares)	2,619,872		2,274,147
Operating Partnership, as General Partner or Managing Member
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Series A Preferred OP Units (in shares)	3,328,873		3,328,873
Operating Partnership, as General Partner or Managing Member | Series A Preferred Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Series A Preferred OP Units (in shares)	188		188
Operating Partnership, as General Partner or Managing Member | Series C Preferred Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Series A Preferred OP Units (in shares)	136,593		136,593
Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	$ 648,440	$ 589,548
Distributions declared of $0.27 and $0.26 per Common OP Unit for three months ended March 31, 2018 and 2017, respectively	(1,721)	(1,617)
Net income (loss)	(11,579)	4,340
Conversion of Common OP Units to Common Shares by limited partners of the Operating Partnership	(642)	(438)
Other comprehensive income - unrealized loss on valuation of swap agreements	1,160	(296)
Reclassification of realized interest on swap agreements	94	141
Noncontrolling interest contributions		20,269
Noncontrolling interest distributions	(695)	(3,822)
Employee Long-term Incentive Plan Unit Awards	3,716	4,141
Rebalancing adjustment	1,225	5,693
Ending Balance	639,998	617,959
Noncontrolling Interests | Restatement Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ending Balance	1,225
Noncontrolling Interests | Noncontrolling Interests in Partially-Owned Affiliates
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	545,519	494,126
Distributions declared of $0.27 and $0.26 per Common OP Unit for three months ended March 31, 2018 and 2017, respectively	0	0
Net income (loss)	(12,191)	3,278
Conversion of Common OP Units to Common Shares by limited partners of the Operating Partnership	0	0
Other comprehensive income - unrealized loss on valuation of swap agreements	886	(317)
Reclassification of realized interest on swap agreements	84	92
Noncontrolling interest contributions		20,269
Noncontrolling interest distributions	(695)	(3,822)
Employee Long-term Incentive Plan Unit Awards	0	0
Rebalancing adjustment		0
Ending Balance	533,603	513,626
Noncontrolling Interests | Noncontrolling Interests in Partially-Owned Affiliates | Restatement Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ending Balance	0
Noncontrolling Interests | Operating Partnership, as General Partner or Managing Member
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	102,921	95,422
Distributions declared of $0.27 and $0.26 per Common OP Unit for three months ended March 31, 2018 and 2017, respectively	(1,721)	(1,617)
Net income (loss)	612	1,062
Conversion of Common OP Units to Common Shares by limited partners of the Operating Partnership	(642)	(438)
Other comprehensive income - unrealized loss on valuation of swap agreements	274	21
Reclassification of realized interest on swap agreements	10	49
Noncontrolling interest contributions		0
Noncontrolling interest distributions	0	0
Employee Long-term Incentive Plan Unit Awards	3,716	4,141
Rebalancing adjustment		5,693
Ending Balance	106,395	$ 104,333
Noncontrolling Interests | Operating Partnership, as General Partner or Managing Member | Restatement Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ending Balance	$ 1,225

Shareholders' Equity, Noncont71

Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Preferred OP Units (Details)	3 Months Ended	12 Months Ended		27 Months Ended	231 Months Ended
	Mar. 31, 2018USD ($)$ / Unitsshares	Dec. 31, 2016$ / sharesshares	Dec. 31, 1999shares	Mar. 31, 2018USD ($)$ / Unitsshares	Mar. 31, 2018USD ($)$ / Unitsshares	Dec. 31, 2017shares
Class of Stock [Line Items]
Denominator for Series A Preferred OP Unit conversion | $	$ 7.50			$ 7.50	$ 7.50
Preferred OP Units
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)	0
Series A Preferred Stock
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)			1,580
Preferred stock, stated value per unit | $ / Units	1,000
Per unit conversion amount, Series A Preferred OP Units (in dollars per unit) | $ / Units	22.50			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
Operating Partnership, as General Partner or Managing Member
Class of Stock [Line Items]
Preferred OP Units (in shares)	3,328,873			3,328,873	3,328,873	3,328,873
Operating Partnership, as General Partner or Managing Member | Series A Preferred Stock
Class of Stock [Line Items]
Preferred OP Units (in shares)	188			188	188	188
Operating Partnership, as General Partner or Managing Member | Series C Preferred Stock
Class of Stock [Line Items]
Preferred OP Units (in shares)	136,593			136,593	136,593	136,593
Gotham Plaza | Preferred OP Units
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)		141,593
Gotham Plaza | Series C Preferred Stock
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
Gotham Plaza | Common Shares
Class of Stock [Line Items]
Issuance of common shares, net of issuance costs (in Shares)		442,478
Share price (in dollars per share) | $ / shares		$ 100
Preferred quarterly distribution per share price | $ / shares		$ 0.9375
Number of convertible units if share price falls below $28.80 (in shares)		3.4722
Number of convertible units of share price falls above $35.20 (in Shares)		2.8409
Minimum | Gotham Plaza | Preferred OP Units
Class of Stock [Line Items]
Share price at conversion date | $ / shares		$ 28.80
Maximum | Gotham Plaza | Preferred OP Units
Class of Stock [Line Items]
Share price at conversion date | $ / shares		$ 35.20

Leases - Operating Leases (Deta

Leases - Operating Leases (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)shopping_center	Mar. 31, 2017USD ($)
Operating Leased Assets [Line Items]
Number of shopping centers with land leases | shopping_center	7
Ground lease expense	$ 0.4	$ 0.8
Rent expense capitalized	0.2	0.1
Rent expense	$ 0.2	$ 0.2
Minimum
Operating Leased Assets [Line Items]
Operating lease term	1 month
Period of lease term	25 years
Maximum
Operating Leased Assets [Line Items]
Operating lease term	99 years
Period of lease term	71 years

Leases - Capital Leasers (Detai

Leases - Capital Leasers (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Capital Leased Assets [Line Items]
Capital lease obligation	$ 70,732		$ 70,611
991 Madison Avenue New York, NY
Capital Leased Assets [Line Items]
Capital lease term	49 years
Capital lease obligation	$ 76,600
991 Madison Avenue New York, NY | Capital Lease Obligations
Capital Leased Assets [Line Items]
Repayments capital lease obligations	$ 600	$ 600

Leases - Lease Obligations (Det

Leases - Lease Obligations (Details) $ in Thousands	Mar. 31, 2018USD ($)
Minimum Rental Revenues
2,018	$ 125,069
2,019	169,873
2,020	155,238
2,021	135,874
2,022	116,972
Thereafter	527,122
Total	1,230,148
Minimum Rental Payments
2,018	4,546
2,019	4,565
2,020	4,256
2,021	4,364
2,022	4,400
Thereafter	183,911
Total	$ 206,042

Segment Reporting (Details)

Segment Reporting (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)segment	Mar. 31, 2017USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment	3
Revenues	$ 63,124	$ 61,999
Depreciation and amortization	(28,576)	(24,536)
Property operating expenses, other operating and real estate taxes	(19,377)	(19,097)
General and administrative expenses	(8,470)	(8,469)
Operating income	6,701	9,897
Interest income	3,737	8,984
Equity in earnings (losses) of unconsolidated affiliates	1,684	12,703
Interest expense	(15,890)	(11,488)
Income tax provision	(392)	(125)
Net (loss) income	(4,160)	19,971
Net loss (income) attributable to noncontrolling interests	11,579	(4,340)
Net income attributable to Acadia	7,419	15,631
Real estate at cost	3,529,805	3,463,566
Total assets	3,938,976	4,020,589
Cash paid for acquisition of real estate	46,171	34,688
Cash paid for development and property improvement costs	18,136	27,015
Operating segments | Core Portfolio
Segment Reporting Information [Line Items]
Revenues	41,628	44,446
Depreciation and amortization	(15,498)	(16,439)
Property operating expenses, other operating and real estate taxes	(10,894)	(12,853)
General and administrative expenses	0	0
Operating income	15,236	15,154
Interest income	0	0
Equity in earnings (losses) of unconsolidated affiliates	1,426	560
Interest expense	(6,502)	(7,155)
Income tax provision	0	0
Net (loss) income	10,160	8,559
Net loss (income) attributable to noncontrolling interests	(73)	(432)
Net income attributable to Acadia	10,087	8,127
Real estate at cost	2,042,280	1,983,365
Total assets	2,283,451	2,246,037
Cash paid for acquisition of real estate	1,337	0
Cash paid for development and property improvement costs	5,946	996
Operating segments | Funds
Segment Reporting Information [Line Items]
Revenues	21,496	17,553
Depreciation and amortization	(13,078)	(8,097)
Property operating expenses, other operating and real estate taxes	(8,483)	(6,244)
General and administrative expenses	0	0
Operating income	(65)	3,212
Interest income	0	0
Equity in earnings (losses) of unconsolidated affiliates	258	12,143
Interest expense	(9,388)	(4,333)
Income tax provision	0	0
Net (loss) income	(9,195)	11,022
Net loss (income) attributable to noncontrolling interests	11,652	(3,908)
Net income attributable to Acadia	2,457	7,114
Real estate at cost	1,487,525	1,480,201
Total assets	1,546,566	1,498,045
Cash paid for acquisition of real estate	44,834	34,688
Cash paid for development and property improvement costs	12,190	26,019
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
Operating income	0	0
Interest income	3,737	8,984
Equity in earnings (losses) of unconsolidated affiliates	0	0
Interest expense	0	0
Income tax provision	0	0
Net (loss) income	3,737	8,984
Net loss (income) attributable to noncontrolling interests	0	0
Net income attributable to Acadia	3,737	8,984
Real estate at cost	0	0
Total assets	108,959	276,507
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	(8,470)	(8,469)
Operating income	(8,470)	(8,469)
Interest income	0	0
Equity in earnings (losses) of unconsolidated affiliates	0	0
Interest expense	0	0
Income tax provision	(392)	(125)
Net (loss) income	(8,862)	(8,594)
Net loss (income) attributable to noncontrolling interests	0	0
Net income attributable to Acadia	(8,862)	(8,594)
Real estate at cost	0	0
Total assets	0	0
Cash paid for acquisition of real estate	0	0
Cash paid for development and property improvement costs	$ 0	$ 0

Share Incentive and Other Com76

Share Incentive and Other Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 0.1	$ 0.1
Trustee fees	0.3	0.3
Total unrecognized compensation cost related to nonvested awards	$ 21
Weighted-average period over which cost is expected to be recognized	1 year 11 months
LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	33.30%
Award vesting period	3 years
Total fair value of shares that vested	$ 8.8		$ 7.3
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
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of shares that vested	$ 0.7		0.7
LTIP Units and Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total value of restricted shares and LTIP units as of the grant date	$ 10.6
Unit based compensation			$ 8.4
Weighted average grant date fair value, grants (in dollars per share)	$ 27.26		$ 31.69
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
Officer | 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
Officer | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures	5,768
Trustee | LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures	11,105
Trustee | LTIP Units | Tranche 1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures	5,805
Trustee | LTIP Units | Tranche 2
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures	5,300
General and Administrative Expense | LTIP Units and Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit based compensation	$ 2.2	1.9
Trustee | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures	11,814
Shares granted to trustees for trustee fees vesting on one year anniversary of grant date	3,864
Shares granted to trustees for trustee fees begin vesting on two year anniversary of grant date	7,950
Trustee | LTIP Units and Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Annual vesting rate of shares granted to trustees that begin vesting on the second anniversary of grant date	33.00%
Second Amended 2016 Plan | Officers and Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	1,223,815
Long Term Investment Alignment Program | Senior Executives
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	$ 0.3
Long Term Investment Alignment Program | Fund III | Senior Executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of promote awarded as share based compensation award				25.00%
Long Term Investment Alignment Program | Fund IV | Senior Executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of promote awarded as share based compensation award				22.80%
Minimum | LTIP Units and Restricted Stock | 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%
Minimum | LTIP Units and Restricted Stock | 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%
Maximum | LTIP Units and Restricted Stock | 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%
Maximum | LTIP Units and Restricted Stock | 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%

Share Incentive and Other Com77

Share Incentive and Other Compensation - Schedule of Unvested Shares and LTIP Units (Details) - $ / shares	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Shares unvested, Beginning of period (in shares)	41,327	46,499
Shares granted (in shares)	5,768	19,442
Shares vested (in shares)	(12,784)	(23,430)
Shares forfeited (in shares)	(47)	(1,184)
Shares unvested, End of period (in shares)	34,264	41,327
Weighted Grant-Date Fair Value
Shares unvested, Weighted average grant date fair value, Beginning of period (in dollars per share)	$ 26.92	$ 27.58
Shares granted, Weighted average grant date fair value (in dollars per share)	25.96	29.85
Shares vested, Weighted average grant date fair value (in dollars per share)	31.21	30.47
Shares forfeited, Weighted average grant date fair value (in dollars per share)	35.37	32.65
Shares unvested, Weighted average grant date fair value, End of period (in dollars per share)	$ 25.14	$ 26.92
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
Shares granted (in shares)	381,821	310,551
Shares vested (in shares)	(288,913)	(257,124)
Shares forfeited (in shares)	0	(205)
Shares unvested, End of period (in shares)	1,003,007	910,099
Weighted Grant-Date Fair Value
Shares unvested, Weighted average grant date fair value, Beginning of period (in dollars per share)	$ 28.28	$ 26.99
Shares granted, Weighted average grant date fair value (in dollars per share)	27.28	31.80
Shares vested, Weighted average grant date fair value (in dollars per share)	30.34	28.27
Shares forfeited, Weighted average grant date fair value (in dollars per share)	0	32.49
Shares unvested, Weighted average grant date fair value, End of period (in dollars per share)	$ 27.30	$ 28.28

Share Incentive and Other Com78

Share Incentive and Other Compensation - Employee Share Purchase Plan and Deferred Share Plan (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 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)	943	841

Share Incentive and Other Com79

Share Incentive and Other Compensation - Employee 401 (k) Plan (Details)	3 Months Ended
	Mar. 31, 2018USD ($)
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Employer matching contribution	50.00%
Maximum annual contribution per employee	6.00%
Maximum employee annual salary contribution	15.00%
Maximum employee annual salary contribution amount	$ 18,000

Earnings Per Common Share (Deta

Earnings Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Numerator:
Net income attributable to Acadia	$ 7,419	$ 15,631
Less: net income attributable to participating securities	(44)	(162)
Income from continuing operations net of income attributable to participating securities	$ 7,375	$ 15,469
Denominator:
Weighted average shares for basic earnings per share (in shares)	83,434,083	83,634,727
Effect of dilutive securities:
Employee unvested restricted shares (in shares)	4,394	10,730
Denominator for diluted earnings per share (in shares)	83,438,477	83,645,457
Basic and diluted earnings per share (in dollars per share)	$ 0.09	$ 0.18
Series A Preferred OP Units
Anti-Dilutive Shares Excluded from Denominator:
Antidilutive securities excluded from computation of earnings per share (in shares)	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
Series C Preferred OP Units
Anti-Dilutive Shares Excluded from Denominator:
Antidilutive securities excluded from computation of earnings per share (in shares)	136,593	141,593
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	471,035

Subsequent Events (Details)

Subsequent Events (Details) - USD ($)	Apr. 23, 2018	Apr. 30, 2018	Mar. 31, 2018	Apr. 30, 2018	Dec. 31, 2017	Apr. 17, 2018
Subsequent Event [Line Items]
Stock repurchase authorized amount			$ 200,000,000
Shares repurchased during period			$ 31,961,000
Number of shares repurchased during period (in shares)			1,304,194		0
Subsequent Event
Subsequent Event [Line Items]
Shares repurchased during period		$ 21,800,000		$ 53,800,000
Number of shares repurchased during period (in shares)		936,541		2,240,735
Subsequent Event | Fund II
Subsequent Event [Line Items]
Capital distribution	$ 15,000,000
Subsequent Event | Fund II | Partnership Interest
Subsequent Event [Line Items]
Capital distribution	$ 4,300,000
Subsequent Event | Disposed of by sale | Sherman Avenue [Member] | Fund II
Subsequent Event [Line Items]
Consideration received						$ 26,000,000