Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ 110,122	$ (175,486)	$ 199,589
Other comprehensive income (loss):
Foreign currency translation gain (loss)	69,811	(127,521)	206,784
(Loss) gain on derivative instruments, net of tax of $(3.6) million, $12.7 million and $(22.9) million, respectively	(19,008)	36,799	(33,431)
Pension liability adjustment, net of tax of $(0.6) million, $0.3 million and $0.4 million, respectively	(3,310)	2,463	2,099
Other comprehensive income (loss)	47,493	(88,259)	175,452
Comprehensive income (loss)	157,615	(263,745)	375,041
Comprehensive (income) loss attributable to noncontrolling interests	(1,199)	(264)	246
Comprehensive income (loss) attributable to Acadia Healthcare Company, Inc.	$ 156,416	$ (264,009)	$ 375,287

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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