Investments - Rollforward of changes in allowance for credit losses on available for sale fixed maturity securities by major investment category (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	$ 191	$ 122	$ 98	$ 186
Securities for which allowance for credit losses were not previously recorded	30	21	207	36
Securities sold during the period	(41)	(5)	(42)	(10)
Addition to (release of) the allowance for credit losses on securities that had an allowance recorded in a previous period, for which there was no intent to sell before recovery of amortized cost basis	18	(35)	(66)	(103)
Write-offs charged against the allowance	(22)	(6)	(22)	(12)
Other	(1)	0	0	0
Balance, end of period	175	97	175	97
Structured
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	15	14	8	17
Securities for which allowance for credit losses were not previously recorded	2	6	51	8
Securities sold during the period	(1)	(2)	(1)	(3)
Addition to (release of) the allowance for credit losses on securities that had an allowance recorded in a previous period, for which there was no intent to sell before recovery of amortized cost basis	10	(8)	(32)	(12)
Write-offs charged against the allowance	0	0	0	0
Other	0	0	0	0
Balance, end of period	26	10	26	10
Non-Structured
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	176	108	90	169
Securities for which allowance for credit losses were not previously recorded	28	15	156	28
Securities sold during the period	(40)	(3)	(41)	(7)
Addition to (release of) the allowance for credit losses on securities that had an allowance recorded in a previous period, for which there was no intent to sell before recovery of amortized cost basis	8	(27)	(34)	(91)
Write-offs charged against the allowance	(22)	(6)	(22)	(12)
Other	(1)	0	0	0
Balance, end of period	$ 149	$ 87	$ 149	$ 87

Debt Securities Available For Sale Allowance For Credit Loss Other.

No definition available.

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Balance Type:	credit
Period Type:	duration

- 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

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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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.

+ 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 (f)
-URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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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 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 (d)
-URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455

+ Details

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- Definition

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).

+ 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 (g)
-URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455

+ Details

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- Definition

Amount excluding accrued interest, 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 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

+ Details

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