Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Net Investment Income [Line Items]
Gross investment income	$ 1,331	$ 1,366	$ 2,676	$ 2,746
Less: Investment expenses	90	81	177	164
Net investment income	1,241	1,285	2,499	2,582
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	943	924	1,859	1,848
Trading Securities
Net Investment Income [Line Items]
Gross investment income	8	(1)	5	10
Equity securities
Net Investment Income [Line Items]
Gross investment income	1	1	1	1
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	257	255	512	512
Policy loans
Net Investment Income [Line Items]
Gross investment income	15	19	34	37
Limited partnerships and LLCs
Net Investment Income [Line Items]
Gross investment income	11	80	78	151
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross investment income	63	63	123	135
Other
Net Investment Income [Line Items]
Gross investment income	$ 33	$ 25	$ 64	$ 52

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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