Segment Reporting (Parenthetical) (Detail) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Net revenues		$ 2,475,685	$ 2,409,872	$ 2,430,855	$ 2,449,798	$ 2,315,239	$ 2,227,655	$ 2,275,204	$ 2,225,353	$ 9,766,210	$ 9,043,451	$ 8,205,088
Behavioral Health Services
Segment Reporting Information [Line Items]
Net revenues	[1]									4,645,007	4,400,335	4,012,216
Behavioral Health Services | Located in U.K.
Segment Reporting Information [Line Items]
Net revenues										$ 241,000	$ 203,000	$ 45,000

[1] Includes net revenues generated from our behavioral health care facilities located in the U.K. amounting to approximately $241 million in 2016, $203 million in 2015 and $45 million in 2014.