Investments (Amortized Cost And Fair Value Of Fixed Maturity Securities, By Contractual Maturity) (Details) - Fixed Maturity Securities [Member] - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Investment [Line Items]
Due in one year or less, Estimated Fair Value	$ 720
Due after one year through five years, Estimated Fair Value	7,095
Due after five years through ten years, Estimated Fair Value	8,703
Due after ten years, Estimated Fair Value	5,645
Mortgage-backed securities, Estimated Fair Value	4,541
Available for sale securities Fair Value	26,704	$ 26,899
Due in one year or less, Amortized Cost	726
Due after one year through five years, Amortized Cost	7,489
Due after five years through ten years, Amortized Cost	9,512
Due after ten years, Amortized Cost	6,255
Mortgage-backed securities, Amortized Cost	5,033
Available For Sale Securities, Amortized Cost	$ 29,015	$ 26,257

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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