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]
Other investments	$ (37)	$ (38)	$ 75
Investment income	5,694	6,323	5,676
Investment expense	(606)	(611)	(402)
Net investment income	5,088	5,712	5,274
Fixed maturity AFS securities, at fair value
Net Investment Income [Line Items]
Gross investment income	4,088	4,961	4,408
Trading securities
Net Investment Income [Line Items]
Gross investment income	117	158	179
Equity securities
Net Investment Income [Line Items]
Gross investment income	21	13	11
Mortgage loans on real estate
Net Investment Income [Line Items]
Gross investment income	881	752	687
Policy loans
Net Investment Income [Line Items]
Gross investment income	93	102	100
Cash and invested cash
Net Investment Income [Line Items]
Gross investment income	227	118	12
Commercial mortgage loan prepayment and bond makewhole premiums
Net Investment Income [Line Items]
Gross investment income	15	10	100
Alternative investments
Net Investment Income [Line Items]
Gross investment income	289	244	96
Consent fees
Net Investment Income [Line Items]
Gross investment income	$ 0	$ 3	$ 8

Gross Investment Income Including Derivatives, Operating

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Gross Investment Income, Operating, Net

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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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