Acquisitions and Dispositions - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) Hospital	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($) Hospital
Business Acquisition [Line Items]
Pretax gain (loss) before tax	$ (5)
Proceeds from sale of business	193	$ 1,237	$ 2,160
Real Estate and Other Investments [Member]
Business Acquisition [Line Items]
Pretax gain (loss) before tax		274	394
Pretax gain (loss) after tax		$ 200	$ 294
Discontinued Operation, Gain (Loss) on Disposal, Statement of Income or Comprehensive Income [Extensible Enumeration]		Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property	Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property
Proceeds from sale of business	31	$ 326	$ 658
Discontinued Operations, Disposed of by Sale [Member]
Business Acquisition [Line Items]
Pretax gain (loss) before tax		1,027
Pretax gain (loss) after tax		$ 527
Discontinued Operation, Gain (Loss) on Disposal, Statement of Income or Comprehensive Income [Extensible Enumeration]		Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property
Proceeds from sale of business		$ 911
Hospital Facility [Member]
Business Acquisition [Line Items]
Aggregate purchase price	$ 229		$ 67
Number of hospitals purchased | Hospital	4		2
Proceeds from sale of business	$ 162
Number of hospitals sold | Hospital	2
Hospital Facility [Member] | Southern Georgia [Member]
Business Acquisition [Line Items]
Number of hospitals purchased | Hospital			1
Hospital Facility [Member] | TENNESSEE
Business Acquisition [Line Items]
Number of hospitals purchased | Hospital			1
Hospital Facility [Member] | Discontinued Operations, Disposed of by Sale [Member] | Southern Georgia [Member]
Business Acquisition [Line Items]
Number of hospitals sold | Hospital			2
Hospital Facility [Member] | Discontinued Operations, Disposed of by Sale [Member] | GEORGIA
Business Acquisition [Line Items]
Pretax gain (loss) before tax			$ 1,226
Pretax gain (loss) after tax			$ 920
Discontinued Operation, Gain (Loss) on Disposal, Statement of Income or Comprehensive Income [Extensible Enumeration]			Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property
Proceeds from sale of business			$ 1,502
Number of hospitals sold | Hospital			5
Hospital Facility [Member] | Discontinued Operations, Disposed of by Sale [Member] | Northern Georgia [Member]
Business Acquisition [Line Items]
Number of hospitals sold | Hospital			3
Nonhospital Health Care [Member]
Business Acquisition [Line Items]
Aggregate purchase price	$ 406	224	$ 114
Fair value of the noncontrolling interest in the acquiree at the acquisition date		72	117
Other [Member]
Business Acquisition [Line Items]
Goodwill	$ 362	$ 262	1,002
Urgent Care Centers [Member]
Business Acquisition [Line Items]
Aggregate purchase price			594
Home Health and Hospice [Member]
Business Acquisition [Line Items]
Fair value of the noncontrolling interest in the acquiree at the acquisition date			100
Payment to acquire venture providing post acute care services			$ 330
Business acquisition percentage of voting interests acquired			80.00%