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	$ 5,445	$ 4,917	$ 4,313
Less: Investment expenses	345	357	249
Net investment income	5,100	4,560	4,064
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	3,708	3,481	3,044
Equity securities
Net Investment Income [Line Items]
Gross investment income	3	2	2
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	1,000	957	840
Policy loans
Net Investment Income [Line Items]
Gross investment income	48	45	42
Limited partnerships and LLCs
Net Investment Income [Line Items]
Gross investment income	357	167	263
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross investment income	225	181	56
Other
Net Investment Income [Line Items]
Gross investment income	$ 104	$ 84	$ 66

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