Investments (Net Investment Income) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net Investment Income [Line Items]
Less: Investment expenses	$ 2,262	$ 1,284	$ 949
Net investment income	19,908	15,916	21,395
Securities Investment
Net Investment Income [Line Items]
Gross Investment Income, Operating	20,987	18,498	21,392
Net investment income	18,725	17,214	20,443
Fixed maturity securities AFS
Net Investment Income [Line Items]
Gross Investment Income, Operating	12,990	11,490	10,996
Equity Securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	32	36	36
FVO securities
Net Investment Income [Line Items]
Net investment income	188	(127)	167
Mortgage loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	4,761	3,539	3,435
Policy loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	471	460	474
Real Estate and Real Estate Joint Ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	438	1,200	954
OLPI
Net Investment Income [Line Items]
Gross Investment Income, Operating	454	858	4,927
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	1,011	358	103
Operating joint ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	38	51	77
Other Investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	604	633	223
Unit-linked investments
Net Investment Income [Line Items]
Net investment income	$ 1,183	$ (1,298)	$ 952

Amount, before investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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