Investments - Rollforward of credit loss allowance for bank loans (Details) - Bank loans - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Rollforward of the valuation allowance on impaired mortgage loans
Beginning balance	$ (16)	$ 0
Net decreases (increases) related to credit losses	6	(4)
Reduction of allowance related to sales	3	3
Write-offs	0	1
Ending balance	(7)	(16)
Accounting Standards Update 2016-13
Rollforward of the valuation allowance on impaired mortgage loans
Beginning balance	$ 0	(16)
Ending balance		$ 0

Finance Receivables, Allowance for Credit Loss, Securities Sold

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- Definition

Amount, after recovery, of writeoff of financing receivable, charged against allowance for credit loss.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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- Definition

Amount of increase (decrease) in allowance for credit loss on financing receivable.

+ References

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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

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