Investments (Exposure To Concentrations Of Credit Risk) (Details) - USD ($) $ in Millions	Dec. 31, 2022		Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Available for Sale at Fair value - Amortized cost	$ 59,663		$ 55,873
Fixed maturity securities available-for-sale at fair value (amortized cost of $59,663 and $55,873; allowance for credit losses of $37 and $31)	52,901	[1]	60,749	[2]
JAPAN
Debt Securities, Available-for-sale [Line Items]
Available for Sale at Fair value - Amortized cost	2,988		3,080
Fixed maturity securities available-for-sale at fair value (amortized cost of $59,663 and $55,873; allowance for credit losses of $37 and $31)	2,516		3,063
Canadian Province Of Ontario Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available for Sale at Fair value - Amortized cost	1,436		1,377
Fixed maturity securities available-for-sale at fair value (amortized cost of $59,663 and $55,873; allowance for credit losses of $37 and $31)	1,649		2,347
Canadian Province Of Quebec Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available for Sale at Fair value - Amortized cost	982		1,092
Fixed maturity securities available-for-sale at fair value (amortized cost of $59,663 and $55,873; allowance for credit losses of $37 and $31)	$ 1,068		$ 1,451

[1] Excludes limited partnerships that are measured at estimated fair value using the NAV per share (or its equivalent) as a practical expedient. As of December 31, 2022, the fair value of such investments was $683 million

[2] Excludes limited partnerships that are measured at estimated fair value using the NAV per share (or its equivalent) as a practical expedient. As of December 31, 2021, the fair value of such investments was $581 million.