Revenue - Schedule of Revenue and Percentage Generated by Each Payor Type (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Health Care Organization, Receivable and Revenue Disclosures [Line Items]
Revenue	$ 616,653	$ 551,199
U.S. Facilities [Member]
Health Care Organization, Receivable and Revenue Disclosures [Line Items]
Revenue	$ 616,653	$ 551,199
Revenue, Percentage	100.00%	100.00%
U.S. Facilities [Member] | Commercial [Member]
Health Care Organization, Receivable and Revenue Disclosures [Line Items]
Revenue	$ 194,693	$ 162,702
Revenue, Percentage	31.60%	29.50%
U.S. Facilities [Member] | Medicare [Member]
Health Care Organization, Receivable and Revenue Disclosures [Line Items]
Revenue	$ 94,582	$ 86,185
Revenue, Percentage	15.30%	15.60%
U.S. Facilities [Member] | Medicaid [Member]
Health Care Organization, Receivable and Revenue Disclosures [Line Items]
Revenue	$ 299,914	$ 274,620
Revenue, Percentage	48.60%	49.80%
U.S. Facilities [Member] | Self-Pay [Member]
Health Care Organization, Receivable and Revenue Disclosures [Line Items]
Revenue	$ 19,785	$ 22,443
Revenue, Percentage	3.20%	4.10%
U.S. Facilities [Member] | Other [Member]
Health Care Organization, Receivable and Revenue Disclosures [Line Items]
Revenue	$ 7,679	$ 5,249
Revenue, Percentage	1.30%	1.00%