Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Net Investment Income [Line Items]
Gross investment income	$ 1,393	$ 1,349	$ 4,082	$ 4,020
Less: Investment expenses	84	91	246	263
Net investment income	1,309	1,258	3,836	3,757
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	917	941	2,744	2,777
Trading securities (1)
Net Investment Income [Line Items]
Gross investment income	14	0	24	0
Equity securities
Net Investment Income [Line Items]
Gross investment income	0	0	1	2
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	256	252	767	747
Policy loans
Net Investment Income [Line Items]
Gross investment income	11	12	36	35
Limited partnerships and LLCs
Net Investment Income [Line Items]
Gross investment income	108	56	259	228
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross investment income	59	63	173	157
Other
Net Investment Income [Line Items]
Gross investment income	$ 28	$ 25	$ 78	$ 74

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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