Loans and Leases - Schedule Of Troubled Debt Restructurings Within The Previous 12 Months (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022 USD ($) loan	Jun. 30, 2021 USD ($) loan	Jun. 30, 2022 USD ($) loan	Jun. 30, 2021 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	9	12	20	23
Recorded Investment \| $	$ 1	$ 11	$ 1	$ 14
Consumer \| Credit card and other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	1	1	9	1
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 0
C&I \| Commercial \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	2	5	5	12
Recorded Investment \| $	$ 0	$ 1	$ 0	$ 2
CRE \| Commercial \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	0	2	0	2
Recorded Investment \| $	$ 0	$ 9	$ 0	$ 9
HELOC \| Consumer \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	0	0	0	1
Recorded Investment \| $	$ 0	$ 0	$ 0	$ 0
Real estate installment loans \| Consumer \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	6	4	6	7
Recorded Investment \| $	$ 1	$ 1	$ 1	$ 3

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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 https://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 https://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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