Investments - Equity Security Investments (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Dec. 31, 2023
Cost
Equity securities with readily determinable fair values	$ 647	$ 656
Equity securities with no readily determinable fair value	3,281	3,248
Total	3,928	3,904
Carrying Value
Equity securities with readily determinable fair values	39	51
Equity securities with no readily determinable fair value	1,532	3,311
Total	$ 1,571	$ 3,362
Equity Securities FV NI \| Product Concentration Risk \| Health Care Sector
Other Commitments [Line Items]
Concentration percentage	90.00%

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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No definition available.

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Equity Securities, FV-NI And Without Readily Determinable Fair Value, And Hybrid Instruments, Carrying Amount

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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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No definition available.

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Equity Securities Without Readily Determinable Fair Value, Amortized Cost

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of investment in equity security without readily determinable fair value.

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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.

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