Investments (Net Investment Income) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Net Investment Income [Line Items]
Gross investment income	$ 4,313	$ 4,962	$ 3,695
Less: Investment expenses	249	147	167
Net investment income	4,064	4,815	3,528
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	3,044	2,794	2,659
Equity securities
Net Investment Income [Line Items]
Gross investment income	2	5	6
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	840	686	663
Policy loans
Net Investment Income [Line Items]
Gross investment income	42	41	34
Limited partnerships and LLCs
Net Investment Income [Line Items]
Gross investment income	263	1,391	240
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross investment income	56	3	41
Other
Net Investment Income [Line Items]
Gross investment income	$ 66	$ 42	$ 52

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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