Real Estate - Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
STATEMENTS OF INCOME
Gain on disposition of properties	$ 24	$ 12,056	$ 509	$ 14,070
Disposal Group, Not Discontinued Operations
STATEMENTS OF INCOME
Revenues		2,099	721	8,972
Expenses	(44)	(2,237)	(982)	(7,738)
Gain on disposition of properties	24	12,056	509	14,070	$ 30,324
Net income attributable to noncontrolling interests	16	(8,943)	(169)	(11,184)
Net income attributable to Acadia	$ (4)	$ 2,975	$ 79	$ 4,120

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

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- Definition

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

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