Investments - Net Investment Income (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Net Investment Income [Line Items]
Gross investment income	$ 2,667	$ 2,396	$ 2,257
Investment expenses	(99)	(91)	(80)
Total net investment income	2,568	2,305	2,177
Total fixed maturities
Net Investment Income [Line Items]
Gross investment income	2,204	1,895	1,469
Equity securities
Net Investment Income [Line Items]
Gross investment income	35	45	57
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	266	235	211
Limited partnerships and other alternative investments
Net Investment Income [Line Items]
Gross investment income	148	212	515
Other investments
Net Investment Income [Line Items]
Gross investment income	$ 14	$ 9	$ 5

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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