Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Net Investment Income [Line Items]
Gross investment income	$ 1,309	$ 1,126
Less: Investment expenses	86	91
Net investment income	1,223	1,035
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	908	830
Equity securities
Net Investment Income [Line Items]
Gross investment income	2	0
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	245	238
Policy loans
Net Investment Income [Line Items]
Gross investment income	9	9
Limited partnerships and LLCs
Net Investment Income [Line Items]
Gross investment income	74	(13)
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross investment income	47	40
Other assets
Net Investment Income [Line Items]
Gross investment income	$ 24	$ 22

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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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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