Loans and Leases - Schedule Of Troubled Debt Restructurings Occurring During The Year (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	145	58	249	110
Pre-Modification Outstanding Recorded Investment	$ 27	$ 25	$ 45	$ 50
Post-Modification Outstanding Recorded Investment	$ 27	$ 25	$ 45	$ 47
Consumer \| Credit card and other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	8	15	9	28
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0	$ 0
C&I \| Commercial \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	0	10	3	27
Pre-Modification Outstanding Recorded Investment	$ 0	$ 19	$ 0	$ 28
Post-Modification Outstanding Recorded Investment	$ 0	$ 19	$ 0	$ 27
CRE \| Commercial \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	0	0	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0	$ 12
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0	$ 10
HELOC \| Consumer \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	42	7	56	19
Pre-Modification Outstanding Recorded Investment	$ 3	$ 0	$ 5	$ 2
Post-Modification Outstanding Recorded Investment	$ 3	$ 0	$ 5	$ 2
Real estate installment loans \| Consumer \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	95	26	181	35
Pre-Modification Outstanding Recorded Investment	$ 24	$ 6	$ 40	$ 8
Post-Modification Outstanding Recorded Investment	$ 24	$ 6	$ 40	$ 8

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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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