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		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	$ 1,452	$ 562	$ 538	$ 474
(Reversal of) provision for loan losses	49	92	850	217
Loans charged-off	(140)	(85)	(272)	(148)
Recoveries of loans previously charged-off	10	4	26	30
Allowance for loan losses, end of period	1,371	573	1,371	573
Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	932	407	354
(Reversal of) provision for loan losses	52	50	590	102
Loans charged-off	(108)	(59)
Recoveries of loans previously charged-off	5	2
Allowance for loan losses, end of period	881	400	881	400
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	520	155	184
(Reversal of) provision for loan losses	(3)	42	260	120
Loans charged-off	(32)	(26)
Recoveries of loans previously charged-off	5	2
Allowance for loan losses, end of period	490	173	490	173
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	0	0
(Reversal of) provision for loan losses	0	0	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			(154)	(84)
Recoveries of loans previously charged-off			15	23
Commercial Loans \| Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period			354	359
Consumer Loans
Allowance for Loan and Lease Losses [Roll Forward]
Loans charged-off			(118)	(64)
Recoveries of loans previously charged-off			11	7
Consumer Loans \| Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period			184	110
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	$ 5
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