Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Net Investment Income [Line Items]
Less: Investment expenses	$ 343	$ 232	$ 858	$ 701
Net investment income	3,585	5,568	11,452	16,162
Securities Investment
Net Investment Income [Line Items]
Gross Investment Income, Operating	4,249	5,686	13,817	16,164
Net investment income	3,906	5,454	12,959	15,463
Fixed maturity securities AFS
Net Investment Income [Line Items]
Gross Investment Income, Operating	2,903	2,759	8,449	8,251
Equity Securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	14	8	26	28
FVO Securities
Net Investment Income [Line Items]
Net investment income	(43)	6	(197)	92
Mortgage loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	899	838	2,556	2,586
Policy loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	115	118	345	359
Real Estate and Real Estate Joint Ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	284	279	991	660
Other limited partnership interests
Net Investment Income [Line Items]
Net investment income	(194)	1,541	900	3,870
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	103	25	183	74
Operating joint ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	12	17	61	55
Other Investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	156	95	503	189
Unit-linked investments
Net Investment Income [Line Items]
Net investment income	$ (321)	$ 114	$ (1,507)	$ 699

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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