Condensed Consolidated Statements of Comprehensive (Loss) Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 34,067	$ 29,511
Other comprehensive loss:
Foreign currency translation (loss) gain	(122,000)	44,481
Gain (loss) on derivative instruments, net of tax of $16.3 million and $(3.5) million, respectively	43,746	(8,690)
Other comprehensive (loss) income	(78,254)	35,791
Comprehensive (loss) income	(44,187)	65,302
Comprehensive income attributable to noncontrolling interests	(604)	(40)
Comprehensive (loss) income attributable to Acadia Healthcare Company, Inc.	$ (44,791)	$ 65,262