Investments - Schedule of Net Investment Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Net Investment Income [Line Items]
Gross investment income before expenses and fees	$ 862	$ 827	$ 1,651	$ 1,589
Expenses and fees	(26)	(25)	(49)	(48)
Net investment income	836	802	1,602	1,541
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income before expenses and fees	592	570	1,148	1,129
Equity securities
Net Investment Income [Line Items]
Gross investment income before expenses and fees	3	3	5	6
Commercial mortgage loans
Net Investment Income [Line Items]
Gross investment income before expenses and fees	75	72	151	145
Policy loans
Net Investment Income [Line Items]
Gross investment income before expenses and fees	36	32	74	68
Limited partnerships
Net Investment Income [Line Items]
Gross investment income before expenses and fees	74	69	112	77
Other invested assets:
Net Investment Income [Line Items]
Gross investment income before expenses and fees	63	62	123	123
Cash, cash equivalents, restricted cash and short-term investments
Net Investment Income [Line Items]
Gross investment income before expenses and fees	$ 19	$ 19	$ 38	$ 41

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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