Investments - Investment Income (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Dec. 31, 2021	Jun. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Net Investment Income [Line Items]
Investment expense	$ (14)	$ (13)	$ (26)	$ (24)
Net investment income	498	534	816	924
Fixed maturities, AFS
Net Investment Income [Line Items]
Gross Investment Income, Operating	174	243	518	586
Equity securities, at fair value
Net Investment Income [Line Items]
Gross Investment Income, Operating	10	2	7	6
Mortgage loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	32	45	92	92
Policy loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	36	40	82	84
Limited partnerships and other alternative investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	259	216	130	161
Other investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	$ 1	$ 1	$ 13	$ 19

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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