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 of recovery of financing receivables doubtful of collection that were previously charged off.

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- Definition

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

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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Loans and Allowance for Loan Losses - Reconciliation of Changes in Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	$ 1,152	$ 516	$ 538	$ 474
(Reversal of) provision for loan losses	353	66	801	125
Loans charged-off	(59)	(35)	(132)	(63)
Recoveries of loans previously charged-off	6	15	16	26
Allowance for loan losses, end of period	1,452	562	1,452	562
Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	679	389	354	359
(Reversal of) provision for loan losses	264	20	538	52
Loans charged-off	(14)	(14)
Recoveries of loans previously charged-off	3	12		21
Allowance for loan losses, end of period	932	407	932	407
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	473	122	184	110
(Reversal of) provision for loan losses	89	51	263	78
Loans charged-off	(45)	(21)
Recoveries of loans previously charged-off	3	3		5
Allowance for loan losses, end of period	520	155	520	155
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	0	5		5
(Reversal of) provision for loan losses	0	(5)	0	(5)
Loans charged-off	0	0	0	0
Recoveries of loans previously charged-off	0	0	0	0
Allowance for loan losses, end of period	$ 0	$ 0	0	0
Commercial Loans
Allowance for Loan and Lease Losses [Roll Forward]
Loans charged-off			(46)	(25)
Recoveries of loans previously charged-off			10
Commercial Loans \| Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period			354
Consumer Loans
Allowance for Loan and Lease Losses [Roll Forward]
Loans charged-off			(86)	$ (38)
Recoveries of loans previously charged-off			6
Consumer Loans \| Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period			184
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period			0
Unallocated \| Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period			0
Cumulative Effect, Period Of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period			229
Cumulative Effect, Period Of Adoption, Adjustment \| Commercial Loans \| Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period			76
Cumulative Effect, Period Of Adoption, Adjustment \| Consumer Loans \| Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period			153
Cumulative Effect, Period Of Adoption, Adjustment \| Unallocated \| Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period			0
Cumulative Effect, Period Of Adoption, Adjusted Balance
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period			767
Cumulative Effect, Period Of Adoption, Adjusted Balance \| Commercial Loans \| Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period			430
Cumulative Effect, Period Of Adoption, Adjusted Balance \| Consumer Loans \| Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period			337
Cumulative Effect, Period Of Adoption, Adjusted Balance \| Unallocated \| Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period			$ 0