Acquisitions and Dispositions - Additional Information (Detail) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($) Hospital	Mar. 31, 2019 USD ($) Hospital
Business Acquisition [Line Items]
Number of hospitals purchased \| Hospital	1	7
Proceeds from sale of business	$ 35	$ 30
Real Estate and Other Investments [Member]
Business Acquisition [Line Items]
Gain (loss) on sales of real estate		5
Hospitals [Member]
Business Acquisition [Line Items]
Aggregate purchase price		1,398
Hospitals [Member] \| Discontinued Operations, Disposed of by Sale [Member]
Business Acquisition [Line Items]
Gain (loss) on sales of real estate	7	(1)
Proceeds from sale of business	35	25
Nonhospital Health Care [Member]
Business Acquisition [Line Items]
Aggregate purchase price		$ 76
Hospital and other nonhospital health care entities [Member]
Business Acquisition [Line Items]
Aggregate purchase price	328
Fair value of identifiable net assets	$ 296

Number of hospitals acquired.

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Amount of assets acquired at the acquisition date.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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