Commitments and Contingencies - Schedule of Changes in General and Professional Liability and Workers Compensation Reserves (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Commitments and Contingencies Disclosure [Line Items]
Beginning balance	$ 368,964	$ 322,824	$ 314,941
Plus: Accrued insurance expense, net of commercial premiums paid	186,215	159,223	105,672
Less: Payments made in settlement of self-insured claims	(91,501)	(113,083)	(97,789)
Ending balance	463,678	368,964	322,824
General and Professional Liability
Commitments and Contingencies Disclosure [Line Items]
Beginning balance	263,779	241,820	243,051
Plus: Accrued insurance expense, net of commercial premiums paid	129,690	91,518	56,452
Less: Payments made in settlement of self-insured claims	(44,776)	(69,559)	(57,683)
Ending balance	348,693	263,779	241,820
Workers’ Compensation
Commitments and Contingencies Disclosure [Line Items]
Beginning balance	105,185	81,004	71,890
Plus: Accrued insurance expense, net of commercial premiums paid	56,525	67,705	49,220
Less: Payments made in settlement of self-insured claims	(46,725)	(43,524)	(40,106)
Ending balance	$ 114,985	$ 105,185	$ 81,004