Investments (Amortized Cost And Fair Value Of Fixed Maturity Securities, By Contractual Maturity) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, Amortized Cost	$ 26,971	$ 25,641
Fixed Maturities [Member]
Debt Securities, Available-for-sale [Line Items]
Due in one year or less, Amortized Cost	1,257
Due after one year through five years, Amortized Cost	6,686
Due after five years through ten years, Amortized Cost	9,225
Due after ten years, Amortized Cost	6,071
Mortgage-backed securities, Amortized Cost	4,344
Available-for-sale securities, Amortized Cost	27,583	26,257
Due in one year or less, Estimated Fair Value	1,254
Due after one year through five years, Estimated Fair Value	6,569
Due after five years through ten years, Estimated Fair Value	8,905
Due after ten years, Estimated Fair Value	5,904
Mortgage-backed securities, Estimated Fair Value	4,183
Available-for-sale securities, Estimated Fair Value	$ 26,815	$ 26,899

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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Amount 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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