Dispositions and Acquisitions - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022
Business Acquisition [Line Items]
Acquisition, cash paid	$ 4	$ 19
Aggregate cash proceeds from divestiture of businesses	$ 24	12
Washington, District of Columbia
Business Acquisition [Line Items]
Acquisition, cash paid		$ 51
Washington, District of Columbia \| Hospital
Business Acquisition [Line Items]
Non-controlling ownership interests by subsidiaries		20.00%

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479907/805-20-50-5

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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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
-Topic 805
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479581/805-30-50-1

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-Section 45
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- Definition

This element represents the cash inflow during the period from the sale of a component of the entity.

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