Number of beds available in micro-hospital.

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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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Dispositions and Acquisitions - Additional Information (Detail) $ in Millions	1 Months Ended	9 Months Ended
	Aug. 31, 2022 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($) Bed
Business Acquisition [Line Items]
Acquisition, cash paid		$ 19
Aggregate cash proceeds from divestiture of businesses		$ 12	$ 21
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%	100.00%
Nevada
Business Acquisition [Line Items]
Acquisition, cash paid			$ 39
Number of beds available in micro-hospital \| Bed			22