Investments - Net Investment Income (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net Investment Income [Line Items]
Other investments	$ (38)	$ 75	$ 60
Investment income	6,323	5,676	6,144
Investment expense	(611)	(402)	(305)
Net investment income	5,712	5,274	5,839
Fixed maturity AFS securities, at fair value
Net Investment Income [Line Items]
Gross investment income	4,961	4,408	4,242
Trading securities
Net Investment Income [Line Items]
Gross investment income	158	179	165
Equity securities
Net Investment Income [Line Items]
Gross investment income	13	11	3
Mortgage loans on real estate
Net Investment Income [Line Items]
Gross investment income	752	687	677
Policy loans
Net Investment Income [Line Items]
Gross investment income	102	100	115
Cash and invested cash
Net Investment Income [Line Items]
Gross investment income	118	12	0
Commercial mortgage loan prepayment and bond makewhole premiums
Net Investment Income [Line Items]
Gross investment income	10	100	195
Alternative investments
Net Investment Income [Line Items]
Gross investment income	244	96	677
Consent fees
Net Investment Income [Line Items]
Gross investment income	$ 3	$ 8	$ 10

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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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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