Investments - Schedule of Portfolio Composition (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Investments [Abstract]
Fixed income securities, at fair value	$ 50,777	$ 48,865
Equity securities, at fair value	2,383	2,411
Mortgage loans, net	815	822
Limited partnership interests	8,562	8,380
Short-term investments, at fair value	4,318	5,144
Other investments, net	1,004	1,055
Total investments	$ 67,859	$ 66,677

Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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), classified as current.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Amount of short-term investments classified as other.

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