Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Net Investment Income [Line Items]
Gross investment income	$ 1,126	$ 1,176
Less: Investment expenses	91	41
Net investment income	1,035	1,135
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	830	709
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	238	202
Policy loans
Net Investment Income [Line Items]
Gross investment income	9	9
Limited partnerships and LLCs
Net Investment Income [Line Items]
Gross investment income	(13)	241
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross investment income	40	1
Other
Net Investment Income [Line Items]
Gross investment income	$ 22	$ 14

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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