Investments (Available-For-Sale Securities By Contractual Maturities) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Available-for-sale Securities, Debt Maturities, Amortized Cost
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	$ 106,974	$ 104,526
Available-for-sale Securities, Debt Maturities, Fair Value
Available-for-sale Securities, Debt Securities, Total	109,921	117,511
Fixed Maturity AFS Securities [Member]
Available-for-sale Securities, Debt Maturities, Amortized Cost
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	106,974	104,526
Available-for-sale Securities, Debt Maturities, Fair Value
Available-for-sale Securities, Debt Securities, Total	109,921	$ 117,511
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	2,877
Due after one year through five years	16,206
Due after five years through ten years	19,655
Due after ten years	55,457
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	94,195
Available-for-sale Securities, Debt Maturities, Fair Value
Due in one year or less	2,877
Due after one year through five years	16,183
Due after five years through ten years	19,532
Due after ten years	58,687
Available-for-sale Securities, Debt Securities, Total	97,279
Structured Securities [Member] \| Fixed Maturity AFS Securities [Member]
Available-for-sale Securities, Debt Maturities, Amortized Cost
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	12,779
Available-for-sale Securities, Debt Maturities, Fair Value
Available-for-sale Securities, Debt Securities, Total	$ 12,642

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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