Amount of increase (decrease) of allowance reserve for credit loss.

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
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Amount of interest income on financing receivable on nonaccrual status.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
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Loans and ACL - Narrative (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
Loans and ACL - Narrative (Details) - USD ($) $ in Millions	Jan. 01, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Receivables [Abstract]
Modifications that defaulted during the period that had been classified as a TDR during the previous 12 months		$ 18	$ 21	$ 39	$ 39
Financing Receivable
Financing Receivable, Nonaccrual, Interest Income		7		15
CECL impact on Allowance for Credit Losses
Financing Receivable
Allowance for Loan and Lease Losses, Period Increase (Decrease)	$ (3,100)
Commercial:
Financing Receivable
Allowance for Loan and Lease Losses, Period Increase (Decrease)		(442)		(853)
Credit card
Financing Receivable
Allowance for Loan and Lease Losses, Period Increase (Decrease)		20		(30)
Commitments to extend, originate or purchase credit
Financing Receivable
Allowance for Loan and Lease Losses, Period Increase (Decrease)		(31)		(22)
Consumer:
Financing Receivable
Allowance for Loan and Lease Losses, Period Increase (Decrease)		$ (69)		$ (199)