Basis of Presentation and Significant Accounting Policies - Schedule of Net Operating Revenues (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Health Care Organization, Receivable and Revenue Disclosures [Line Items]
Net operating revenues	$ 3,086	$ 3,025	$ 9,308	$ 9,069
Medicare
Health Care Organization, Receivable and Revenue Disclosures [Line Items]
Net operating revenues	608	644	1,884	1,928
Medicare Managed Care
Health Care Organization, Receivable and Revenue Disclosures [Line Items]
Net operating revenues	498	479	1,563	1,471
Medicaid
Health Care Organization, Receivable and Revenue Disclosures [Line Items]
Net operating revenues	456	449	1,328	1,362
Managed Care and Other Third Party Payors
Health Care Organization, Receivable and Revenue Disclosures [Line Items]
Net operating revenues	1,479	1,446	4,441	4,248
Self-Pay
Health Care Organization, Receivable and Revenue Disclosures [Line Items]
Net operating revenues	$ 45	$ 7	$ 92	$ 60