Condensed Consolidated Statements of Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Accumulated Deficit [Member]
Balance at Dec. 31, 2020	$ 1,899,456	$ 880	$ 2,580,327	$ (371,365)	$ (310,386)
Balance, shares at Dec. 31, 2020		88,024,000
Common stock issued under stock incentive plans	12,740	$ 7	12,733
Common stock issued under stock incentive plans, shares		705,000
Repurchase of shares for payroll tax withholding, net of proceeds from stock option exercises	(4,521)		(4,521)
Equity-based compensation expense	7,034		7,034
Other	2,208		2,208
Other comprehensive income	371,365			371,365
Net income attributable to Acadia Healthcare Company, Inc.	9,717				9,717
Balance at Mar. 31, 2021	2,297,999	$ 887	2,597,781		(300,669)
Balance, shares at Mar. 31, 2021		88,729,000
Balance at Dec. 31, 2020	$ 1,899,456	$ 880	2,580,327	$ (371,365)	(310,386)
Balance, shares at Dec. 31, 2020		88,024,000
Common stock issued under stock incentive plans, shares	558,322
Balance at Dec. 31, 2021	$ 2,517,489	$ 890	2,636,350		(119,751)
Balance, shares at Dec. 31, 2021	89,028,158	89,028,000
Balance at Mar. 31, 2021	$ 2,297,999	$ 887	2,597,781		(300,669)
Balance, shares at Mar. 31, 2021		88,729,000
Common stock issued under stock incentive plans	5,622	$ 2	5,620
Common stock issued under stock incentive plans, shares		188,000
Repurchase of shares for payroll tax withholding, net of proceeds from stock option exercises	(580)		(580)
Equity-based compensation expense	9,031		9,031
Net income attributable to Acadia Healthcare Company, Inc.	44,514				44,514
Balance at Jun. 30, 2021	2,356,586	$ 889	2,611,852		(256,155)
Balance, shares at Jun. 30, 2021		88,917,000
Common stock issued under stock incentive plans	3,255	$ 1	3,254
Common stock issued under stock incentive plans, shares		89,000
Repurchase of shares for payroll tax withholding, net of proceeds from stock option exercises	(444)		(444)
Equity-based compensation expense	8,923		8,923
Net income attributable to Acadia Healthcare Company, Inc.	66,126				66,126
Balance at Sep. 30, 2021	2,434,446	$ 890	2,623,585		(190,029)
Balance, shares at Sep. 30, 2021		89,006,000
Common stock issued under stock incentive plans	412		412
Common stock issued under stock incentive plans, shares		22,000
Repurchase of shares for payroll tax withholding, net of proceeds from stock option exercises	(189)		(189)
Equity-based compensation expense	12,542		12,542
Net income attributable to Acadia Healthcare Company, Inc.	70,278				70,278
Balance at Dec. 31, 2021	$ 2,517,489	$ 890	2,636,350		(119,751)
Balance, shares at Dec. 31, 2021	89,028,158	89,028,000
Common stock issued under stock incentive plans	$ 3,749	$ 7	3,742
Common stock issued under stock incentive plans, shares	110,559	633,000
Repurchase of shares for payroll tax withholding, net of proceeds from stock option exercises	$ (15,490)		(15,490)
Equity-based compensation expense	7,925		7,925
Net income attributable to Acadia Healthcare Company, Inc.	60,837				60,837
Balance at Mar. 31, 2022	$ 2,574,510	$ 897	$ 2,632,527		$ (58,914)
Balance, shares at Mar. 31, 2022	89,661,341	89,661,000