Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Net Investment Income [Line Items]
Less: Investment expenses	$ 526	$ 568
Net investment income	4,885	5,436
Securities Investment
Net Investment Income [Line Items]
Gross Investment Income, Operating	5,638	5,462
Net investment income	5,112	4,894
Fixed maturity securities AFS
Net Investment Income [Line Items]
Gross Investment Income, Operating	3,467	3,288
Equity Securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	9	7
FVO securities
Net Investment Income [Line Items]
Net investment income	(20)	85
Mortgage loans (1)
Net Investment Income [Line Items]
Gross Investment Income, Operating	1,139	1,194
Policy loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	107	113
Real Estate and Real Estate Joint Ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	207	10
OLPI (1)
Net Investment Income [Line Items]
Gross Investment Income, Operating	220	301
Cash, cash equivalents and short-term investments (1)
Net Investment Income [Line Items]
Gross Investment Income, Operating	250	291
Operating joint ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	20	22
Other Investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	239	151
Unit-linked investments
Net Investment Income [Line Items]
Net investment income	$ (227)	$ 542

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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