Segment Reporting (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2017 USD ($) segment	Mar. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment	3
Revenues	$ 61,999	$ 48,045
Depreciation and amortization	(24,536)	(16,849)
Property operating expenses, other operating and real estate taxes	(19,097)	(11,993)
General and administrative expenses	(8,469)	(9,352)
Operating income	9,897	9,851
Gain on disposition of properties	0	65,393
Interest income	8,984	4,638
Equity in earnings of unconsolidated affiliates	12,703	1,954
Interest expense	(11,488)	(8,038)
Income tax (provision) benefit	(125)	77
Net income	19,971	73,875
Net income attributable to noncontrolling interests	(4,340)	(44,950)
Net income attributable to Acadia	15,631	28,925
Real estate at cost	3,463,566	2,746,214
Total assets	4,020,589	3,148,327
Acquisition of real estate	34,688	12,287
Development and property improvement costs	27,015	37,463
Core Portfolio [Member]
Segment Reporting Information [Line Items]
Revenues	44,446	38,107
Depreciation and amortization	(16,439)	(13,495)
Property operating expenses, other operating and real estate taxes	(12,853)	(8,562)
General and administrative expenses	0	0
Operating income	15,154	16,050
Gain on disposition of properties		0
Interest income	0	0
Equity in earnings of unconsolidated affiliates	560	592
Interest expense	(7,155)	(6,764)
Income tax (provision) benefit	0	0
Net income	8,559	9,878
Net income attributable to noncontrolling interests	(432)	(2,822)
Net income attributable to Acadia	8,127	7,056
Real estate at cost	1,983,365	1,641,312
Total assets	2,246,037	1,827,059
Acquisition of real estate	0	0
Development and property improvement costs	996	3,248
Funds
Segment Reporting Information [Line Items]
Revenues	17,553	9,938
Depreciation and amortization	(8,097)	(3,354)
Property operating expenses, other operating and real estate taxes	(6,244)	(3,431)
General and administrative expenses	0	0
Operating income	3,212	3,153
Gain on disposition of properties		65,393
Interest income	0	0
Equity in earnings of unconsolidated affiliates	12,143	1,362
Interest expense	(4,333)	(1,274)
Income tax (provision) benefit	0	0
Net income	11,022	68,634
Net income attributable to noncontrolling interests	(3,908)	(42,128)
Net income attributable to Acadia	7,114	26,506
Real estate at cost	1,480,201	1,104,902
Total assets	1,498,045	1,166,589
Acquisition of real estate	34,688	12,287
Development and property improvement costs	26,019	34,215
Structuring 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
Gain on disposition of properties		0
Interest income	8,984	4,638
Equity in earnings of unconsolidated affiliates	0	0
Interest expense	0	0
Income tax (provision) benefit	0	0
Net income	8,984	4,638
Net income attributable to noncontrolling interests	0	0
Net income attributable to Acadia	8,984	4,638
Real estate at cost	0	0
Total assets	276,507	154,679
Acquisition of real estate	0	0
Development and property improvement costs	0	0
Other
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	(8,469)	(9,352)
Operating income	(8,469)	(9,352)
Gain on disposition of properties		0
Interest income	0	0
Equity in earnings of unconsolidated affiliates	0	0
Interest expense	0	0
Income tax (provision) benefit	(125)	77
Net income	(8,594)	(9,275)
Net income attributable to noncontrolling interests	0	0
Net income attributable to Acadia	(8,594)	(9,275)
Real estate at cost	0	0
Total assets	0	0
Acquisition of real estate	0	0
Development and property improvement costs	$ 0	$ 0