Investments - Equity Securities (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Cost
Equity securities with readily determinable fair values	$ 641	$ 635
Equity securities with no readily determinable fair value	6,167	3,215
Total	6,808	3,850
Carrying Value
Equity securities with readily determinable fair values	134	37
Equity securities with no readily determinable fair value	3,383	524
Total	3,517	$ 561
Shields Health Solutions \| Preferred Stock
Carrying Value
Equity securities with no readily determinable fair value	$ 3,500

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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