Investments (Available-For-Sale Securities By Contractual Maturities) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Available-for-sale Securities, Debt Maturities, Fair Value
Available-for-sale Securities, Debt Securities, Total	$ 104,170	$ 99,465
Fixed Maturity AFS Securities [Member]
Available-for-sale Securities, Debt Maturities, Amortized Cost
Amortized Cost, Total	113,321	110,944
Available-for-sale Securities, Debt Maturities, Fair Value
Available-for-sale Securities, Debt Securities, Total	104,170	$ 99,465
Fixed Maturity AFS Securities Excluding Structured Securities [Member] \| Fixed Maturity AFS Securities [Member]
Available-for-sale Securities, Debt Maturities, Amortized Cost
Due in one year or less	3,242
Due after one year through five years	17,849
Due after five years through ten years	19,493
Due after ten years	56,493
Amortized Cost, Total	97,077
Available-for-sale Securities, Debt Maturities, Fair Value
Due in one year or less	3,204
Due after one year through five years	17,093
Due after five years through ten years	18,074
Due after ten years	50,690
Available-for-sale Securities, Debt Securities, Total	89,061
Structured Securities [Member] \| Fixed Maturity AFS Securities [Member]
Available-for-sale Securities, Debt Maturities, Amortized Cost
Amortized Cost, Total	16,244
Available-for-sale Securities, Debt Maturities, Fair Value
Available-for-sale Securities, Debt Securities, Total	$ 15,109

Amortized cost 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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