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	$ 1,150	$ 1,192
Less: Investment expenses	91	41
Net investment income	1,059	1,151
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	837	718
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	239	203
Policy loans
Net Investment Income [Line Items]
Gross investment income	15	15
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	50	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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