Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Net Investment Income [Line Items]
Gross investment income	$ 1,351	$ 1,309
Less: Investment expenses	82	86
Net investment income	1,269	1,223
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	914	908
Trading securities (1)
Net Investment Income [Line Items]
Gross investment income	11	0
Equity securities
Net Investment Income [Line Items]
Gross investment income	0	2
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	256	245
Policy loans
Net Investment Income [Line Items]
Gross investment income	11	9
Limited partnerships and LLCs
Net Investment Income [Line Items]
Gross investment income	71	74
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross investment income	61	47
Other
Net Investment Income [Line Items]
Gross investment income	$ 27	$ 24

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