Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Net Investment Income [Line Items]
Less: Investment expenses	$ 273	$ 232	$ 515	$ 469
Net investment income	3,583	5,280	7,867	10,594
Securities Investment
Net Investment Income [Line Items]
Gross Investment Income, Operating	4,543	5,134	9,568	10,478
Net investment income	4,270	4,902	9,053	10,009
Fixed maturity securities AFS
Net Investment Income [Line Items]
Gross Investment Income, Operating	2,832	2,739	5,546	5,492
Equity Securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	5	9	12	20
FVO Securities
Net Investment Income [Line Items]
Net investment income	(89)	50	(154)	86
Mortgage loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	833	885	1,657	1,748
Policy loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	114	120	230	241
Real Estate and Real Estate Joint Ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	379	205	707	381
Other limited partnership interests
Net Investment Income [Line Items]
Gross Investment Income, Operating	168	1,047	1,094	2,329
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	49	24	80	49
Operating joint ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	31	15	49	38
Other Investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	221	40	347	94
Unit-linked investments
Net Investment Income [Line Items]
Net investment income	$ (687)	$ 378	$ (1,186)	$ 585

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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