Investments - Schedule of Portfolio Composition (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Investments [Abstract]
Fixed income securities, at fair value	$ 51,993	$ 52,747
Equity securities, at fair value	4,465	4,463
Mortgage loans, net	770	784
Limited partnership interests	9,380	9,255
Short-term investments, at fair value	6,541	4,537
Other investments, net	901	824
Total investments	$ 74,050	$ 72,610

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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Sum of the carrying amounts as of the balance sheet date of all investments.

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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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