Credit Quality - Summary of the Nonperforming Loans and Leases by Class (Parenthetical) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Modifications [Line Items]
Loans and leases held for sale	$ 1,223	$ 607
Portfolio loans and leases	109,225	95,086
Commercial Portfolio Segment
Financing Receivable, Modifications [Line Items]
Portfolio loans and leases	70,366	59,571
Nonaccrual
Financing Receivable, Modifications [Line Items]
Loans and leases held for sale	13	16
Portfolio loans and leases	133	120
Nonaccrual \| Government Insured
Financing Receivable, Modifications [Line Items]
Portfolio loans and leases	15	6
Restructured nonaccrual loans and leases	$ 10	$ 2

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Amount of financing receivable modified as troubled debt restructuring.

+ References

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The face amount of loans that will be sold to other entities.

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

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