Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Net Investment Income [Line Items]
Less: Investment expenses	$ 568	$ 461
Net investment income	5,436	4,645
Securities Investment
Net Investment Income [Line Items]
Gross Investment Income, Operating	5,462	4,802
Net investment income	4,894	4,341
Fixed maturity securities AFS
Net Investment Income [Line Items]
Gross Investment Income, Operating	3,288	3,139
Equity Securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	7	12
FVO securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	85	48
Mortgage loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	1,194	1,041
Policy loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	113	119
Real Estate and Real Estate Joint Ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	10	26
OLPI
Net Investment Income [Line Items]
Gross Investment Income, Operating	301	25
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	291	217
Operating joint ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	22	19
Other Investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	151	156
Unit-linked investments
Net Investment Income [Line Items]
Net investment income	$ 542	$ 304

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.

+ References

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