Loans and Leases - Schedule Of Troubled Debt Restructurings Occurring During The Year (Details) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($) loan	Dec. 31, 2020 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	196	368
Pre-Modification Outstanding Recorded Investment	$ 66	$ 236
Post-Modification Outstanding Recorded Investment	$ 61	$ 228
Consumer \| Credit card and other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	51	56
Pre-Modification Outstanding Recorded Investment	$ 0	$ 1
Post-Modification Outstanding Recorded Investment	$ 0	$ 1
C&I (a) \| Commercial \| C&I
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	32	112
Pre-Modification Outstanding Recorded Investment	$ 37	$ 195
Post-Modification Outstanding Recorded Investment	$ 34	$ 188
CRE (b) \| Commercial \| Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	1	19
Pre-Modification Outstanding Recorded Investment	$ 12	$ 15
Post-Modification Outstanding Recorded Investment	$ 10	$ 15
HELOC (c) \| Consumer \| Consumer real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	25	64
Pre-Modification Outstanding Recorded Investment	$ 3	$ 5
Post-Modification Outstanding Recorded Investment	$ 3	$ 5
Real estate installment loans \| Consumer \| Consumer real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	87	117
Pre-Modification Outstanding Recorded Investment	$ 14	$ 20
Post-Modification Outstanding Recorded Investment	$ 14	$ 19

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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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