Loans and Leases - Schedule Of Troubled Debt Restructurings Occurring During The Year (Details) $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($) loan	Mar. 31, 2021 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	104	52
Pre-Modification Outstanding Recorded Investment	$ 18	$ 24
Post-Modification Outstanding Recorded Investment	$ 18	$ 22
Consumer \| Credit card and other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	1	13
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 0
C&I \| Commercial \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	3	17
Pre-Modification Outstanding Recorded Investment	$ 0	$ 8
Post-Modification Outstanding Recorded Investment	$ 0	$ 8
CRE \| Commercial \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 12
Post-Modification Outstanding Recorded Investment	$ 0	$ 10
HELOC \| Consumer \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	14	12
Pre-Modification Outstanding Recorded Investment	$ 2	$ 2
Post-Modification Outstanding Recorded Investment	$ 2	$ 2
Real estate installment loans \| Consumer \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	86	9
Pre-Modification Outstanding Recorded Investment	$ 16	$ 2
Post-Modification Outstanding Recorded Investment	$ 16	$ 2

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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 http://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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