Investments - Investment Income (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Dec. 31, 2021	Jun. 30, 2021	Dec. 31, 2022	Dec. 31, 2020
Net Investment Income [Line Items]
Other	$ 1	$ 1	$ (146)	$ 13
Investment expense	(14)	(13)	(30)	(26)
Net investment income	498	534	778	816
Fixed Maturities, FVO
Net Investment Income [Line Items]
Gross investment income	174	243	620	518
Equity securities, at fair value
Net Investment Income [Line Items]
Gross investment income	10	2	10	7
Mortgage loan
Net Investment Income [Line Items]
Gross investment income	32	45	74	92
Policy loans
Net Investment Income [Line Items]
Gross investment income	36	40	82	82
Limited partnerships and other alternative investments
Net Investment Income [Line Items]
Gross investment income	$ 259	$ 216	$ 168	$ 130

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.2)
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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.2)
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(2))
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+ References

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