Investments - Investment Income (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Dec. 31, 2021	Jun. 30, 2021	Dec. 31, 2023	Dec. 31, 2022
Net Investment Income [Line Items]
Other	$ 1	$ 1	$ (381)	$ (146)
Investment expense	(14)	(13)	(21)	(30)
Total net investment income	498	534	590	778
Fixed maturities
Net Investment Income [Line Items]
Gross investment income	174	243	695	620
Equity securities
Net Investment Income [Line Items]
Gross investment income	10	2	11	10
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	32	45	80	74
Policy loans
Net Investment Income [Line Items]
Gross investment income	36	40	90	82
Investment funds
Net Investment Income [Line Items]
Gross investment income	$ 259	$ 216	$ 116	$ 168

Investment Income, Other

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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 of expenses related to the generation of investment income.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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