Investments - Schedule of Portfolio Composition (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Investments [Abstract]
Fixed income securities, at fair value	$ 57,186	$ 52,747
Equity securities, at fair value	5,338	4,463
Mortgage loans, net	831	784
Limited partnership interests	9,213	9,255
Short-term investments, at fair value	8,743	4,537
Other investments, net	1,017	824
Total investments	$ 82,328	$ 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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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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