Payroll Protection Program loans

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

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

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Amount of financing receivable on nonaccrual status with no allowance for credit loss.

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Amount of increase from purchase of financing receivable.

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Amount of interest income from net investment in sales-type and direct financing leases.

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Present value of lease payments not yet received by lessor and amount expected to be derived from underlying asset, following end of lease term guaranteed by lessee or other third party unrelated to lessor, from sales-type and direct financing leases.

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Loans and the Allowance for Credit Losses (Narrative) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payroll Protection Program loans	$ 2,900
Financing Receivable, Allowance for Credit Loss	1,684	$ 2,425
Accounts Receivable, Allowance for Credit Loss, Period Increase (Decrease)	(609)
Federal Home Loan Bank [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Pledged loans	15,200
Federal Reserve Bank [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Pledged loans	12,800
Indirect-other consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Purchase	532	$ 902
Commercial And Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Sales-type and direct financing lease receivable	1,200
Sales-Type and Direct Financing	31
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Nonaccrual, No Allowance	$ 203		$ 112