Investments - Net Investment Income (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net Investment Income [Line Items]
Investment expenses	$ (80)	$ (71)	$ (83)
Total net investment income	2,313	1,846	1,951
Total fixed maturities
Net Investment Income [Line Items]
Gross investment income	1,349	1,442	1,559
Equity securities
Net Investment Income [Line Items]
Gross investment income	73	39	46
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	181	172	165
Limited partnerships and other alternative investments
Net Investment Income [Line Items]
Gross investment income	732	222	232
Other investments
Net Investment Income [Line Items]
Gross investment income	$ 58	$ 42	$ 32

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.

+ References

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