Investments (ACL for Fixed Maturity Securities AFS By Sector) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	$ 261	$ 99	$ 91	$ 81
ACL not previously recorded	5	18	292	54
Changes for securities with previously recorded ACL	(18)	(2)	(24)	(8)
Securities sold or exchanged	(39)	(32)	(128)	(44)
DebtSecuritiesAvailableforsaleAllowanceforCreditLossReversalRelatedtoBusinessDisposition	0	(2)	0	(2)
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation	(11)	0	(11)	0
Write-offs	0	(13)	(22)	(13)
Allowance, end of period	198	68	198	68
U.S. corporate
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	28	39	30	44
ACL not previously recorded	0	18	13	18
Changes for securities with previously recorded ACL	2	0	17	3
Securities sold or exchanged	0	(26)	(8)	(34)
DebtSecuritiesAvailableforsaleAllowanceforCreditLossReversalRelatedtoBusinessDisposition	0	0	0	0
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation	0	0	0	0
Write-offs	0	(13)	(22)	(13)
Allowance, end of period	30	18	30	18
Foreign corporate
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	53	32	28	16
ACL not previously recorded	0	0	67	25
Changes for securities with previously recorded ACL	(1)	(2)	1	(7)
Securities sold or exchanged	(39)	(6)	(83)	(10)
DebtSecuritiesAvailableforsaleAllowanceforCreditLossReversalRelatedtoBusinessDisposition	0	0	0	0
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation	0	0	0	0
Write-offs	0	0	0	0
Allowance, end of period	13	24	13	24
Foreign government
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	166	21	19	21
ACL not previously recorded	0	0	207	0
Changes for securities with previously recorded ACL	(19)	0	(42)	0
Securities sold or exchanged	0	0	(37)	0
DebtSecuritiesAvailableforsaleAllowanceforCreditLossReversalRelatedtoBusinessDisposition	0	(2)	0	(2)
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation	(11)	0	(11)	0
Write-offs	0	0	0	0
Allowance, end of period	136	19	136	19
CMBS
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance, beginning of period	14	7	14	0
ACL not previously recorded	5	0	5	11
Changes for securities with previously recorded ACL	0	0	0	(4)
Securities sold or exchanged	0	0	0	0
DebtSecuritiesAvailableforsaleAllowanceforCreditLossReversalRelatedtoBusinessDisposition	0	0	0	0
Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation	0	0	0	0
Write-offs	0	0	0	0
Allowance, end of period	$ 19	$ 7	$ 19	$ 7

Debt Securities Available for sale Allowance for Credit Loss, Foreign Currency Translation

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- Definition

Debt Securities Available for sale Allowance for Credit Loss Reversal Related to Business Disposition

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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
-SubTopic 30
-Section 50
-Paragraph 9
-Subparagraph (i)
-URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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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Amount of expense 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), for which no credit loss was previously recorded.

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Amount of expense (reversal of expense) for 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), not intended to be sold and not more likely than not will be required to sell before recovery of amortized cost basis, with previously recorded allowance.

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Amount of decrease in 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) from sale.

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Amount of writeoff 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).

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