Loans and Leases - Schedule Of Troubled Debt Restructurings Within The Previous 12 Months (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($) loan	Sep. 30, 2020 USD ($) loan	Sep. 30, 2021 USD ($) loan	Sep. 30, 2020 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	12	14	35	45
Recorded Investment \| $	$ 14	$ 1	$ 28	$ 1
Consumer \| Credit Card and Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	1	7	2	21
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 0
C&I \| Commercial \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	6	0	18	0
Recorded Investment \| $	$ 3	$ 0	$ 5	$ 0
CRE \| Commercial \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	4	0	6	0
Recorded Investment \| $	$ 10	$ 0	$ 19	$ 0
HELOC \| Consumer \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	0	1	1	8
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 0
Real estate installment loans \| Consumer \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	1	6	8	16
Recorded Investment \| $	$ 1	$ 1	$ 4	$ 1

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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=123577603&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=123577603&loc=SL6953682-111524

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