Segment Reporting (Parenthetical) (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Segment Reporting Information [Line Items]
Net revenues		$ 3,562,774	$ 3,336,027	$ 10,578,430	$ 9,952,390
Total assets		13,873,470	13,378,900	13,873,470	13,378,900	$ 13,494,188
Behavioral Health Services
Segment Reporting Information [Line Items]
Net revenues	[1]	1,542,695	1,434,828	4,575,378	4,235,215
Total assets	[1]	7,372,995	7,336,437	7,372,995	7,336,437
Behavioral Health Services | Located in U.K.
Segment Reporting Information [Line Items]
Net revenues		203,000	167,000	561,000	516,000
Total assets		$ 1,260,000	$ 1,119,000	$ 1,260,000	$ 1,119,000

[1] Includes net revenues generated from our behavioral health care facilities located in the U.K. amounting to approximately $203 million and $167 million for the three-month periods ended September 30, 2023 and 2022, respectively, and approximately $561 million and $516 million for the nine-month periods ended September 30, 2023 and 2022, respectively. Total assets at our U.K. behavioral health care facilities were approximately $1.260 billion and $1.119 billion as of September 30, 2023 and 2022, respectively.