Investments (Net Investment Income) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Net Investment Income [Line Items]
Less: Investment expenses	$ 1,284	$ 949	$ 1,054
Net investment income	15,916	21,395	17,117
Securities Investment
Net Investment Income [Line Items]
Gross Investment Income, Operating	18,498	21,392	17,603
Net investment income	17,214	20,443	16,549
Fixed maturity securities AFS
Net Investment Income [Line Items]
Gross Investment Income, Operating	11,490	10,996	11,304
Equity Securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	36	36	50
FVO Securities
Net Investment Income [Line Items]
Net investment income	(127)	167	140
Mortgage loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	3,539	3,435	3,518
Policy loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	460	474	498
Real Estate and Real Estate Joint Ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	1,200	954	532
Other limited partnership interests
Net Investment Income [Line Items]
Gross Investment Income, Operating	858	4,927	1,000
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	358	103	213
Operating joint ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	51	77	93
Other Investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	633	223	255
Unit-linked investments
Net Investment Income [Line Items]
Net investment income	$ (1,298)	$ 952	$ 568

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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