Acquisitions and Dispositions - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Business Acquisition [Line Items]
Proceeds from sale of business	$ 20	$ 35
Real Estate and Other Investments [Member]
Business Acquisition [Line Items]
Pretax gain (loss) before tax	2	7
Proceeds from sale of business	20	35
Nonhospital Health Care [Member]
Business Acquisition [Line Items]
Aggregate purchase price	$ 22	$ 328

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

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