Investments (ACL for Fixed Maturity Securities AFS by Sector) (Details) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($)
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance , beginning of period	$ 0
ACL not previously recorded	240
Changes for securities with previously recorded ACL	(14)
Securities sold or exchanged	(133)
Securities intended/required to be sold prior to recovery of amortized cost basis	(1)
Disposition (1)	11
Allowance, end of period	81
U.S. corporate
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance , beginning of period	0
ACL not previously recorded	81
Changes for securities with previously recorded ACL	(5)
Securities sold or exchanged	(31)
Securities intended/required to be sold prior to recovery of amortized cost basis	(1)
Disposition (1)	0
Allowance, end of period	44
Foreign government
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance , beginning of period	0
ACL not previously recorded	139
Changes for securities with previously recorded ACL	(5)
Securities sold or exchanged	(102)
Securities intended/required to be sold prior to recovery of amortized cost basis	0
Disposition (1)	11
Allowance, end of period	21
Foreign corporate
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance , beginning of period	0
ACL not previously recorded	18
Changes for securities with previously recorded ACL	(2)
Securities sold or exchanged	0
Securities intended/required to be sold prior to recovery of amortized cost basis	0
Disposition (1)	0
Allowance, end of period	16
RMBS
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance , beginning of period	0
ACL not previously recorded	2
Changes for securities with previously recorded ACL	(2)
Securities sold or exchanged	0
Securities intended/required to be sold prior to recovery of amortized cost basis	0
Disposition (1)	0
Allowance, end of period	$ 0

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No definition available.

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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 http://asc.fasb.org/extlink&oid=121582814&loc=SL82922900-210455

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=121645371&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 http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454

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- Definition

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.

+ References

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- Definition

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 intent to sell or more likely than not will be required to sell before recovery of amortized cost basis.

+ References

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- Definition

Amount of expense (reversal of expense) for expected 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 change in present value of expected cash flows.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82922868-210454

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-Name Accounting Standards Codification
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-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922897-210455

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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