Commitments and Contingencies - Schedule of Changes in General and Professional Liability and Workers Compensation Reserves (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Line Items]
Beginning balance	$ 271,476	$ 259,718	$ 270,088
Liabilities assumed in acquisition	661
Plus: Accrued insurance expense, net of commercial premiums paid	84,638	90,895	59,276	[1]
Less: Payments made in settlement of self-insured claims	(81,960)	(79,137)	(69,646)
Ending balance	274,815	271,476	259,718
General and Professional Liability
Commitments and Contingencies Disclosure [Line Items]
Beginning balance	203,973	192,904	206,290
Liabilities assumed in acquisition	0
Plus: Accrued insurance expense, net of commercial premiums paid	54,671	58,460	22,601	[1]
Less: Payments made in settlement of self-insured claims	(51,185)	(47,391)	(35,987)
Ending balance	207,459	203,973	192,904
Workers’ Compensation
Commitments and Contingencies Disclosure [Line Items]
Beginning balance	67,503	66,814	63,798
Liabilities assumed in acquisition	661
Plus: Accrued insurance expense, net of commercial premiums paid	29,967	32,435	36,675	[1]
Less: Payments made in settlement of self-insured claims	(30,775)	(31,746)	(33,659)
Ending balance	$ 67,356	$ 67,503	$ 66,814

[1] General and professional liability amount is net of adjustment recorded during 2014, as discussed below.