Investments (Amortized Cost And Fair Value Of Fixed Maturity Securities, By Contractual Maturity) (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Due in one year or less, Amortized Cost	$ 1,127
Due after one year through five years, Amortized Cost	8,193
Due after five years through ten years, Amortized Cost	9,466
Due after ten years, Amortized Cost	6,059
Mortgage-backed securities, Amortized Cost	5,879
Available-for-sale securities, Amortized Cost	30,724	$ 29,015
Due in one year or less, Estimated Fair Value	1,118
Due after one year through five years, Estimated Fair Value	7,810
Due after five years through ten years, Estimated Fair Value	8,883
Due after ten years, Estimated Fair Value	5,588
Mortgage-backed securities, Estimated Fair Value	5,397
Available-for-sale securities, Estimated Fair Value	$ 28,796	$ 26,704

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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