Loans and Leases - Schedule Of Troubled Debt Restructurings Within The Previous 12 Months (Details) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) loan	Mar. 31, 2020 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	11	16
Recorded Investment \| $	$ 3	$ 1
Consumer \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	4	9
Recorded Investment \| $	$ 2	$ 1
Consumer \| Credit Card and Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	0	7
Recorded Investment \| $	$ 0	$ 0
C&I \| Commercial \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	7	0
Recorded Investment \| $	$ 1	$ 0
CRE \| Commercial \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	0	0
Recorded Investment \| $	$ 0	$ 0
HELOC \| Consumer \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	1	4
Recorded Investment \| $	$ 0	$ 1
R/E Installment Loans \| Consumer \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	3	5
Recorded Investment \| $	$ 2	$ 0

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953682-111524

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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
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953682-111524

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