Credit Quality and the Allowance for Loan and Lease Losses - Summary of Financial Impacts of Loans That Were Modified for Borrowers Experiencing Financial Difficulty (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2023
Commercial \| Commercial and industrial loans
Financing Receivable, Modifications
Weighted-average length of term extensions	7 months	6 months
Financing receivable, modified, payment deferral, percentage of related loan balance	0.13	0.13
Commercial \| Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
Weighted-average length of term extensions	3 months	18 months
Commercial \| Commercial mortgage nonowner-occupied loans
Financing Receivable, Modifications
Weighted-average length of term extensions	12 months	8 months
Weighted-average interest rate reduction before modification		0.091
Weighted-average interest rate reduction after modification		0.089
Commercial \| Commercial construction loans
Financing Receivable, Modifications
Weighted-average length of term extensions	12 months	12 months
Residential Mortgage
Financing Receivable, Modifications
Weighted-average length of term extensions	171 months	150 months
Financing receivable, modified, payment deferral, percentage of related loan balance	0.17	0.16
Consumer \| Home equity
Financing Receivable, Modifications
Weighted-average length of term extensions	24 years 6 months	24 years 9 months 18 days
Financing receivable, modified, payment deferral, percentage of related loan balance	0.06	0.05
Weighted-average interest rate reduction before modification	0.090	0.086
Weighted-average interest rate reduction after modification	0.072	0.069
Consumer \| Credit card
Financing Receivable, Modifications
Weighted-average interest rate reduction before modification	0.239	0.236
Weighted-average interest rate reduction after modification	0.039	0.038
Consumer \| Other consumer loans
Financing Receivable, Modifications
Financing receivable, modified, payment deferral, percentage of related loan balance	0.05	0.05

Financing Receivable, Modified, Payment Deferral, Percentage Of Related Loan Balance

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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-Name Accounting Standards Codification
-Section 50
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+ References

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-Paragraph 12A
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