Investments (Net Investment Income) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Net Investment Income [Line Items]
Less: Investment expenses	$ 2,248	$ 2,262	$ 1,284
Net investment income	21,273	19,908	15,916
Securities Investment
Net Investment Income [Line Items]
Gross Investment Income, Operating	22,430	20,987	18,498
Net investment income	20,182	18,725	17,214
Fixed maturity securities AFS
Net Investment Income [Line Items]
Gross Investment Income, Operating	13,598	12,990	11,490
Equity Securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	23	32	36
FVO securities
Net Investment Income [Line Items]
Net investment income	205	188	(127)
Mortgage loans (1)
Net Investment Income [Line Items]
Gross Investment Income, Operating	4,734	4,761	3,539
Policy loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	453	471	460
Real Estate and Real Estate Joint Ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	440	438	1,200
OLPI (1)
Net Investment Income [Line Items]
Gross Investment Income, Operating	965	454	858
Cash, cash equivalents and short-term investments (1)
Net Investment Income [Line Items]
Gross Investment Income, Operating	1,122	1,011	358
Operating joint ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	175	38	51
Other Investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	715	604	633
Unit-linked investments
Net Investment Income [Line Items]
Net investment income	$ 1,091	$ 1,183	$ (1,298)

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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