Acquisitions and Dispositions - Additional Information (Detail) $ in Millions	9 Months Ended
Sep. 30, 2020 USD ($) Hospital	Sep. 30, 2019 USD ($) Hospital
Business Acquisition [Line Items]
Number of hospitals purchased \| Hospital	1	7
Proceeds from sale of business	$ 68	$ 49
Real Estate and Other Investments [Member]
Business Acquisition [Line Items]
Gain (loss) on sales of real estate	6	17
Proceeds from sale of business	68	49
Hospitals [Member]
Business Acquisition [Line Items]
Aggregate purchase price		1,399
Nonhospital Health Care [Member]
Business Acquisition [Line Items]
Aggregate purchase price		$ 193
Hospital and other nonhospital health care entities [Member]
Business Acquisition [Line Items]
Aggregate purchase price	380
Fair value of identifiable net assets	$ 309

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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