Schedule of Disaggregates Revenue by Major Source (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disaggregation Of Revenue [Line Items]
Net revenues	$ 15,827,935	$ 14,281,976	$ 13,399,370
Percentage of Net Revenue	100.00%	100.00%	100.00%
Medicare
Disaggregation Of Revenue [Line Items]
Net revenues	$ 1,669,125	$ 1,607,405	$ 1,615,762
Percentage of Net Revenue	11.00%	11.00%	12.00%
Managed Medicare
Disaggregation Of Revenue [Line Items]
Net revenues	$ 1,883,905	$ 1,714,055	$ 1,560,589
Percentage of Net Revenue	12.00%	12.00%	12.00%
Medicaid
Disaggregation Of Revenue [Line Items]
Net revenues	$ 2,252,030	$ 1,532,904	$ 1,512,396
Percentage of Net Revenue	14.00%	11.00%	11.00%
Managed Medicaid
Disaggregation Of Revenue [Line Items]
Net revenues	$ 2,303,938	$ 2,290,661	$ 2,206,855
Percentage of Net Revenue	15.00%	16.00%	16.00%
Managed Care (HMO and PPOs)
Disaggregation Of Revenue [Line Items]
Net revenues	$ 4,496,402	$ 4,211,194	$ 4,012,954
Percentage of Net Revenue	28.00%	29.00%	30.00%
UK Revenue
Disaggregation Of Revenue [Line Items]
Net revenues	$ 880,148	$ 761,124	$ 684,594
Percentage of Net Revenue	6.00%	5.00%	5.00%
Other Patient Revenue and Adjustments, Net
Disaggregation Of Revenue [Line Items]
Net revenues	$ 1,112,808	$ 981,203	$ 745,642
Percentage of Net Revenue	7.00%	7.00%	6.00%
Other Non-patient Revenue
Disaggregation Of Revenue [Line Items]
Net revenues	$ 1,229,579	$ 1,183,430	$ 1,060,578
Percentage of Net Revenue	8.00%	8.00%	8.00%
Acute Care Hospital Services
Disaggregation Of Revenue [Line Items]
Net revenues	$ 8,922,327	$ 8,081,402	$ 7,646,749
Percentage of Net Revenue	100.00%	100.00%	100.00%
Acute Care Hospital Services | Medicare
Disaggregation Of Revenue [Line Items]
Net revenues	$ 1,361,167	$ 1,297,084	$ 1,289,425
Percentage of Net Revenue	15.00%	16.00%	17.00%
Acute Care Hospital Services | Managed Medicare
Disaggregation Of Revenue [Line Items]
Net revenues	$ 1,478,331	$ 1,368,284	$ 1,274,719
Percentage of Net Revenue	17.00%	17.00%	17.00%
Acute Care Hospital Services | Medicaid
Disaggregation Of Revenue [Line Items]
Net revenues	$ 1,106,728	$ 638,986	$ 719,870
Percentage of Net Revenue	12.00%	8.00%	9.00%
Acute Care Hospital Services | Managed Medicaid
Disaggregation Of Revenue [Line Items]
Net revenues	$ 619,262	$ 716,380	$ 757,488
Percentage of Net Revenue	7.00%	9.00%	10.00%
Acute Care Hospital Services | Managed Care (HMO and PPOs)
Disaggregation Of Revenue [Line Items]
Net revenues	$ 2,861,956	$ 2,658,890	$ 2,536,818
Percentage of Net Revenue	32.00%	33.00%	33.00%
Acute Care Hospital Services | UK Revenue
Disaggregation Of Revenue [Line Items]
Net revenues	$ 0	$ 0	$ 0
Percentage of Net Revenue	0.00%	0.00%	0.00%
Acute Care Hospital Services | Other Patient Revenue and Adjustments, Net
Disaggregation Of Revenue [Line Items]
Net revenues	$ 498,749	$ 452,781	$ 261,879
Percentage of Net Revenue	6.00%	6.00%	3.00%
Acute Care Hospital Services | Other Non-patient Revenue
Disaggregation Of Revenue [Line Items]
Net revenues	$ 996,134	$ 948,997	$ 806,550
Percentage of Net Revenue	11.00%	12.00%	11.00%
Behavioral Health Services
Disaggregation Of Revenue [Line Items]
Net revenues	$ 6,895,051	$ 6,190,921	$ 5,729,758
Percentage of Net Revenue	100.00%	100.00%	100.00%
Behavioral Health Services | Medicare
Disaggregation Of Revenue [Line Items]
Net revenues	$ 307,958	$ 310,321	$ 326,337
Percentage of Net Revenue	4.00%	5.00%	6.00%
Behavioral Health Services | Managed Medicare
Disaggregation Of Revenue [Line Items]
Net revenues	$ 405,574	$ 345,771	$ 285,870
Percentage of Net Revenue	6.00%	6.00%	5.00%
Behavioral Health Services | Medicaid
Disaggregation Of Revenue [Line Items]
Net revenues	$ 1,145,302	$ 893,918	$ 792,526
Percentage of Net Revenue	17.00%	14.00%	14.00%
Behavioral Health Services | Managed Medicaid
Disaggregation Of Revenue [Line Items]
Net revenues	$ 1,684,676	$ 1,574,281	$ 1,449,367
Percentage of Net Revenue	24.00%	25.00%	25.00%
Behavioral Health Services | Managed Care (HMO and PPOs)
Disaggregation Of Revenue [Line Items]
Net revenues	$ 1,634,446	$ 1,552,304	$ 1,476,136
Percentage of Net Revenue	24.00%	25.00%	26.00%
Behavioral Health Services | UK Revenue
Disaggregation Of Revenue [Line Items]
Net revenues	$ 880,148	$ 761,124	$ 684,594
Percentage of Net Revenue	13.00%	12.00%	12.00%
Behavioral Health Services | Other Patient Revenue and Adjustments, Net
Disaggregation Of Revenue [Line Items]
Net revenues	$ 614,059	$ 528,422	$ 483,763
Percentage of Net Revenue	9.00%	9.00%	8.00%
Behavioral Health Services | Other Non-patient Revenue
Disaggregation Of Revenue [Line Items]
Net revenues	$ 222,888	$ 224,780	$ 231,165
Percentage of Net Revenue	3.00%	4.00%	4.00%
Other
Disaggregation Of Revenue [Line Items]
Net revenues	$ 10,557	$ 9,653	$ 22,863
Other | Other Non-patient Revenue
Disaggregation Of Revenue [Line Items]
Net revenues	$ 10,557	$ 9,653	$ 22,863