Investments (Fixed Maturity Securities Pledged And Received As Collateral) (Details) - USD ($) $ in Millions	Mar. 31, 2023		Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Available for Sale at Fair value - Amortized cost	$ 61,494		$ 59,663
Fixed maturity securities, available-for-sale	56,085	[1]	52,901	[2]
Collateral Fixed Maturity Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available for Sale at Fair value - Amortized cost	414		355
Fixed maturity securities, available-for-sale	366		292
Collateral Received Fixed Maturity Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, available-for-sale	1,506		1,428
Reported Value Measurement [Member]
Debt Securities, Available-for-sale [Line Items]
Assets Held-in-trust	31,586		31,510
Estimate of Fair Value Measurement [Member]
Debt Securities, Available-for-sale [Line Items]
Assets Held-in-trust	$ 28,622		$ 27,817

[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 March 31, 2023, the fair value of such investments was $726 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, 2022, the fair value of such investments was $683 million