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

Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Gross

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Discontinued Operations Gain (Loss) On Extinguishment Of Debt

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Proceeds from Sale of Real Estate Held-for-investment, Gross

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Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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