Investments - Equity Securities (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2024	Dec. 31, 2023
Cost
Equity securities with readily determinable fair values	$ 657	$ 656
Equity securities with no readily determinable fair value	3,117	3,248
Total	3,774	3,904
Carrying Value
Equity securities with readily determinable fair values	49	51
Equity securities with no readily determinable fair value	468	3,311
Total	517	$ 3,362
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	$ 2,700

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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