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)	12 Months Ended
Dec. 31, 2023
Commercial Portfolio Segment \| Commercial and industrial loans
Financing Receivable, Modifications
Weighted-average length of term extensions	11 months
Financing receivable, modified, payment deferral, percentage of related loan balance	0.05
Commercial Portfolio Segment \| Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
Weighted-average length of term extensions	15 months
Commercial Portfolio Segment \| Commercial mortgage nonowner-occupied loans
Financing Receivable, Modifications
Weighted-average length of term extensions	16 months
Commercial Portfolio Segment \| Commercial construction loans
Financing Receivable, Modifications
Weighted-average length of term extensions	12 months
Residential mortgage loans
Financing Receivable, Modifications
Weighted-average length of term extensions	155 months
Financing receivable, modified, payment deferral, percentage of related loan balance	0.17
Consumer \| Home equity
Financing Receivable, Modifications
Weighted-average length of term extensions	24 years 2 months 12 days
Financing receivable, modified, payment deferral, percentage of related loan balance	0.05
Weighted-average interest rate reduction before modification	0.087
Weighted-average interest rate reduction after modification	0.070
Consumer \| Credit card
Financing Receivable, Modifications
Weighted-average interest rate reduction before modification	0.237
Weighted-average interest rate reduction after modification	0.039
Consumer \| Other consumer loans:
Financing Receivable, Modifications
Financing receivable, modified, payment deferral, percentage of related loan balance	0.06

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
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
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-Section 55
-Paragraph 12A
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-URI https://asc.fasb.org//1943274/2147481933/310-10-55-12A

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-34

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+ References

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-SubTopic 10
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-Section 55
-Paragraph 12A
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