Acquisitions and Dispositions - Additional Information (Detail) $ in Millions	3 Months Ended
Mar. 31, 2025 USD ($) Hospital	Mar. 31, 2024 USD ($) Hospital
Business Acquisition [Line Items]
Proceeds from sale of business	$ 161	$ 310
Hospital Facility [Member]
Business Acquisition [Line Items]
Aggregate purchase price	$ 190	$ 50
Number of hospitals purchased \| Hospital	2	2
Number of hospitals sold \| Hospital	1	1
Proceeds from sale of business	$ 157	$ 297
Pretax gain (loss) before tax	4	193
Healthcare Entity [Member]
Business Acquisition [Line Items]
Aggregate purchase price	37	46
Real Estate and Other Investments [Member]
Business Acquisition [Line Items]
Proceeds from sale of business	$ 1	13
Pretax gain (loss) before tax		$ 8

Number of hospitals acquired.

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- Definition

Number of hospitals sold.

+ References

No definition available.

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- Definition

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.

+ References

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

+ References

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

+ References

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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.

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