Investments - Rollforward of credit loss allowance for mortgage loans (Details) - Mortgage loans on real estate - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ (6)	$ (67)	$ (3)
Net decreases related to credit losses	(1)	40	(39)
Reduction of allowance related to sales	0	21	17
Write-offs	0	0	0
Ending balance	(7)	(6)	(67)
Discontinued Operations, Held-for-sale
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Roll Forward]
Beginning balance		(59)
Ending balance			(59)
Cumulative effect of change in accounting principle
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 0	0	(42)
Ending balance		$ 0	$ 0

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

No definition available.

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

+ Details

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from sale of loan. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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- Definition

Amount, excluding accrued interest, of increase (decrease) in allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

+ Details

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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