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, 2023
Commercial \| Commercial and industrial loans
Financing Receivable, Modifications
Weighted-average length of term extensions	5 months
Commercial \| Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
Weighted-average length of term extensions	4 months
Commercial \| Commercial mortgage nonowner-occupied loans
Financing Receivable, Modifications
Weighted-average length of term extensions	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
Residential Mortgage
Financing Receivable, Modifications
Weighted-average length of term extensions	130 months
Financing receivable, modified, payment deferral, percentage of related loan balance	0.16
Consumer \| Home equity
Financing Receivable, Modifications
Weighted-average length of term extensions	24 years 9 months 18 days
Weighted-average interest rate reduction before modification	0.080
Weighted-average interest rate reduction after modification	0.065
Financing receivable, modified, payment deferral, percentage of related loan balance	0.06
Consumer \| Credit card
Financing Receivable, Modifications
Weighted-average interest rate reduction before modification	0.232
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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- Definition

Financing Receivable, Modified, Weighted Average Interest Rate After Modification

+ References

No definition available.

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- Definition

Financing Receivable, Modified, Weighted Average Interest Rate Before Modification

+ References

No definition available.

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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
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-42

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-42

Reference 3: 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

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-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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- Definition

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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