Investments - Equity Securities (Details) - USD ($) $ in Millions	2 Months Ended
Mar. 31, 2024	Mar. 31, 2025	Dec. 31, 2024
Cost
Equity securities with readily determinable fair values		$ 637	$ 635
Equity securities with no readily determinable fair value		3,217	3,215
Total		3,854	3,850
Carrying Value
Equity securities with readily determinable fair values		38	37
Equity securities with no readily determinable fair value		521	524
Total		$ 559	$ 561
VillageMD
Carrying Value
Amount of impairments or value changes resulting from observable price changes on equity securities with no readily available fair value still held	$ 1,800

Equity Securities, FV-NI And Without Readily Determinable Fair Value, And Hybrid Instruments, Amortized Cost

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Equity Securities, FV-NI And Without Readily Determinable Fair Value, And Hybrid Instruments, Amortized Cost

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Equity Securities, FV-NI And Without Readily Determinable Fair Value, And Hybrid Instruments, Carrying Amount, Before Reclassification To Disposal Group, Assets Held For Sale

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Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

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