Loans and Leases - Schedule Of Troubled Debt Restructurings Occurring During The Year (Details) $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	367
Pre-Modification Outstanding Recorded Investment	$ 91
Post-Modification Outstanding Recorded Investment	$ 85
Consumer: \| Credit card and other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	81
Pre-Modification Outstanding Recorded Investment	$ 12
Post-Modification Outstanding Recorded Investment	$ 12
C&I \| Commercial: \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	6
Pre-Modification Outstanding Recorded Investment	$ 30
Post-Modification Outstanding Recorded Investment	$ 24
CRE \| Commercial: \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	1
Pre-Modification Outstanding Recorded Investment	$ 1
Post-Modification Outstanding Recorded Investment	$ 1
HELOC \| Consumer: \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	98
Pre-Modification Outstanding Recorded Investment	$ 7
Post-Modification Outstanding Recorded Investment	$ 7
Real estate installment loans \| Consumer: \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	181
Pre-Modification Outstanding Recorded Investment	$ 41
Post-Modification Outstanding Recorded Investment	$ 41

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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