Investments (ACL for Fixed Maturity Securities AFS by Sector) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	$ 91	$ 81
ACL not previously recorded	292	85
Changes for securities with previously recorded ACL	(29)	2
Securities sold or exchanged	(139)	(62)
DebtSecuritiesAvailableforsaleAllowanceforCreditLossReversalRelatedtoBusinessDisposition	0	(2)
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation	(10)	0
Write-offs	(22)	(13)
Allowance, end of period	183	91
U.S. corporate
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	30	44
ACL not previously recorded	13	48
Changes for securities with previously recorded ACL	17	3
Securities sold or exchanged	(9)	(52)
DebtSecuritiesAvailableforsaleAllowanceforCreditLossReversalRelatedtoBusinessDisposition	0	0
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation	0	0
Write-offs	(22)	(13)
Allowance, end of period	29	30
Foreign corporate
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	28	16
ACL not previously recorded	67	26
Changes for securities with previously recorded ACL	2	(4)
Securities sold or exchanged	(93)	(10)
DebtSecuritiesAvailableforsaleAllowanceforCreditLossReversalRelatedtoBusinessDisposition	0	0
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation	1	0
Write-offs	0	0
Allowance, end of period	5	28
Foreign government
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	19	21
ACL not previously recorded	207	0
Changes for securities with previously recorded ACL	(48)	0
Securities sold or exchanged	(37)	0
DebtSecuritiesAvailableforsaleAllowanceforCreditLossReversalRelatedtoBusinessDisposition	0	(2)
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation	(11)	0
Write-offs	0	0
Allowance, end of period	130	19
CMBS
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	14	0
ACL not previously recorded	5	11
Changes for securities with previously recorded ACL	0	3
Securities sold or exchanged	0	0
DebtSecuritiesAvailableforsaleAllowanceforCreditLossReversalRelatedtoBusinessDisposition	0	0
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation	0	0
Write-offs	0	0
Allowance, end of period	$ 19	$ 14

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- Definition

Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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