Investments (Maturities of Fixed Maturity Securities) (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Available-for-sale Securities, Debt Maturities [Abstract]
Amortized Cost, Due in one year or less	$ 12,288
Amortized Cost, Due after one year through five years	48,556
Amortized Cost, Due after five years through ten years	53,248
Amortized Cost, Due after ten years	128,624
Amortized Cost, Structured Securities	72,621
Amortized Cost, net of ACL	315,337
Estimated Fair Value, Due in one year or less	12,275
Estimated Fair Value, Due after one year through five years	48,436
Estimated Fair Value, Due after five years through ten years	51,736
Estimated Fair Value, Due after ten years	109,307
Estimated Fair Value, Structured Securities	69,981
Estimated Fair Value of Fixed Maturity Securities AFS	$ 291,735	$ 281,043

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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