Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Net Investment Income [Line Items]
Less: Investment expenses	$ 681	$ 273	$ 1,142	$ 515
Net investment income	5,072	3,583	9,717	7,867
Securities Investment
Net Investment Income [Line Items]
Gross Investment Income, Operating	5,458	4,543	10,260	9,568
Net investment income	4,777	4,270	9,118	9,053
Fixed maturity securities AFS
Net Investment Income [Line Items]
Gross Investment Income, Operating	3,228	2,832	6,367	5,546
Equity Securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	10	5	22	12
FVO Securities
Net Investment Income [Line Items]
Net investment income	50	(89)	98	(154)
Mortgage loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	1,306	833	2,347	1,657
Policy loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	119	114	238	230
Real Estate and Real Estate Joint Ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	137	379	163	707
OLPI
Net Investment Income [Line Items]
Gross Investment Income, Operating	225	168	250	1,094
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	248	49	465	80
Operating joint ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	13	31	32	49
Other Investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	122	221	278	347
Unit-linked investments
Net Investment Income [Line Items]
Net investment income	$ 295	$ (687)	$ 599	$ (1,186)

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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