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
Mar. 31, 2024	Mar. 31, 2023
Commercial \| Commercial and industrial loans
Financing Receivable, Modifications
Weighted-average length of term extensions	5 months	5 months
Financing receivable, modified, payment deferral, percentage of related loan balance	26.00%
Commercial \| Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
Weighted-average length of term extensions	3 months	4 months
Commercial \| Commercial mortgage nonowner-occupied loans
Financing Receivable, Modifications
Weighted-average length of term extensions	6 months	8 months
Commercial \| Commercial construction loans
Financing Receivable, Modifications
Weighted-average length of term extensions		12 months
Residential Mortgage
Financing Receivable, Modifications
Weighted-average length of term extensions	10 years 10 months 24 days	10 years 10 months 24 days
Financing receivable, modified, payment deferral, percentage of related loan balance	12.00%	16.00%
Consumer \| Home equity
Financing Receivable, Modifications
Weighted-average length of term extensions	27 years 1 month 6 days	24 years 9 months 18 days
Financing receivable, modified, payment deferral, percentage of related loan balance	4.00%	6.00%
Weighted-average interest rate reduction before modification	9.10%	8.00%
Weighted-average interest rate reduction after modification	7.30%	6.50%
Consumer \| Credit card
Financing Receivable, Modifications
Weighted-average interest rate reduction before modification	24.10%	23.20%
Weighted-average interest rate reduction after modification	4.20%	3.90%
Consumer \| Other consumer loans
Financing Receivable, Modifications
Financing receivable, modified, payment deferral, percentage of related loan balance	12.00%	6.00%

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

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- Definition

Financing Receivable, Modified, Weighted Average Interest Rate After Modification

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- Definition

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
-Subparagraph (a)(1)
-Publisher FASB
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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
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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-Section 50
-Paragraph 33
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-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-34

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Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481933/310-10-55-12A

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