Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Net Investment Income [Line Items]
Gross investment income	$ 1,322	$ 1,351
Less: Investment expenses	86	82
Net investment income	1,236	1,269
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	905	914
Trading securities
Net Investment Income [Line Items]
Gross investment income	(3)	11
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	255	256
Policy loans
Net Investment Income [Line Items]
Gross investment income	14	11
Limited partnerships and LLCs
Net Investment Income [Line Items]
Gross investment income	67	71
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross investment income	53	61
Other
Net Investment Income [Line Items]
Gross investment income	$ 31	$ 27

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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