Segment Reporting (Parenthetical) (Detail) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Net revenues		$ 2,896,247	$ 2,822,453	$ 2,855,168	$ 2,804,391	$ 2,754,496	$ 2,648,913	$ 2,681,353	$ 2,687,516	$ 11,378,259	$ 10,772,278	$ 10,409,865
Total assets		11,668,250				11,265,480				11,668,250	11,265,480	10,761,828
Provision for asset impairment										97,631	49,310	0
Behavioral Health Services
Segment Reporting Information [Line Items]
Net revenues	[1]									5,210,063	5,038,874	4,906,719
Total assets	[1]	6,910,790				6,786,369				6,910,790	6,786,369	6,648,818
Behavioral Health Services | Located in U.K.
Segment Reporting Information [Line Items]
Net revenues										554,000	505,000	429,000
Total assets		$ 1,270,000				$ 1,224,000				1,270,000	1,224,000	$ 1,098,000
Tradename | Behavioral Health Services
Segment Reporting Information [Line Items]
Provision for intangible asset impairment											$ 49,000
Tradename | Real Property Assets | Behavioral Health Services
Segment Reporting Information [Line Items]
Provision for asset impairment										$ 98,000

[1] Includes net revenues generated from our behavioral health care facilities located in the U.K. amounting to approximately $554 million in 2019, $505 million in 2018 and $429 million in 2017.  Total assets at our U.K. behavioral health care facilities were approximately $1.270 billion as of December 31, 2019, $1.224 billion as of December 31, 2018 and $1.098 billion as of December 31, 2017. In addition, included in our 2019 Behavioral Health Services operating segment Income (loss) before allocation of corporate overhead and income taxes is a pre-tax $98 million provision for asset impairment to reduce the carrying value of a tradename intangible asset and real property assets. Included in our 2018 Behavioral Health Services operating segment Income (loss) before allocation of corporate overhead and income taxes is a pre-tax $49 million provision for asset impairment to reduce the carrying value of a tradename intangible asset.