Loans and Leases - Schedule Of Troubled Debt Restructurings Occurring During The Year (Details) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	368	267
Pre-Modification Outstanding Recorded Investment	$ 236	$ 35
Post-Modification Outstanding Recorded Investment	$ 228	$ 35
Consumer \| Consumer real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	181	178
Pre-Modification Outstanding Recorded Investment	$ 25	$ 20
Post-Modification Outstanding Recorded Investment	$ 24	$ 20
Consumer \| Credit card and other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	56	85
Pre-Modification Outstanding Recorded Investment	$ 1	$ 1
Post-Modification Outstanding Recorded Investment	$ 1	$ 1
C&I \| Commercial \| C&I
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	112	4
Pre-Modification Outstanding Recorded Investment	$ 195	$ 14
Post-Modification Outstanding Recorded Investment	$ 188	$ 14
CRE \| Commercial \| Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	19	0
Pre-Modification Outstanding Recorded Investment	$ 15	$ 0
Post-Modification Outstanding Recorded Investment	$ 15	$ 0
HELOC \| Consumer \| Consumer real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	64	74
Pre-Modification Outstanding Recorded Investment	$ 5	$ 8
Post-Modification Outstanding Recorded Investment	$ 5	$ 8
RE installment loans \| Consumer \| Consumer real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	117	104
Pre-Modification Outstanding Recorded Investment	$ 20	$ 12
Post-Modification Outstanding Recorded Investment	$ 19	$ 12

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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=121611835&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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