Loans and Leases - Schedule Of Troubled Debt Restructurings Occurring During The Year (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022 USD ($) loan	Sep. 30, 2021 USD ($) loan	Sep. 30, 2022 USD ($) loan	Sep. 30, 2021 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	84	21	333	131
Pre-Modification Outstanding Recorded Investment	$ 42	$ 8	$ 87	$ 59
Post-Modification Outstanding Recorded Investment	$ 36	$ 7	$ 81	$ 54
Consumer: \| Credit card and other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	51	8	60	36
Pre-Modification Outstanding Recorded Investment	$ 10	$ 0	$ 10	$ 0
Post-Modification Outstanding Recorded Investment	$ 10	$ 0	$ 10	$ 0
C&I \| Commercial: \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	3	5	6	32
Pre-Modification Outstanding Recorded Investment	$ 30	$ 8	$ 30	$ 37
Post-Modification Outstanding Recorded Investment	$ 24	$ 7	$ 24	$ 34
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	30	2	86	21
Pre-Modification Outstanding Recorded Investment	$ 2	$ 0	$ 6	$ 2
Post-Modification Outstanding Recorded Investment	$ 2	$ 0	$ 6	$ 2
Real estate installment loans \| Consumer: \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	0	6	181	41
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 41	$ 8
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 41	$ 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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