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, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Commercial \| Commercial and industrial loans
Financing Receivable, Modifications
Weighted-average length of term extensions	5 months	7 months	9 months	6 months
Weighted-average length of payment delay	21 months	10 months	13 months	8 months
Commercial \| Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
Weighted-average length of term extensions	6 months	3 months	13 months	18 months
Commercial \| Commercial mortgage nonowner-occupied loans
Financing Receivable, Modifications
Weighted-average length of term extensions	5 months	12 months	7 months	8 months
Commercial \| Commercial construction loans
Financing Receivable, Modifications
Weighted-average length of term extensions	5 months	12 months	9 months	12 months
Residential Mortgage
Financing Receivable, Modifications
Weighted-average length of term extensions	9 years 7 months 6 days	14 years 3 months 18 days	10 years	12 years 6 months
Financing receivable, modified, payment deferral, percentage of related loan balance	13.00%	17.00%	12.00%	16.00%
Consumer \| Home equity
Financing Receivable, Modifications
Weighted-average length of term extensions	22 years 10 months 24 days	24 years 6 months	24 years	24 years 9 months 18 days
Financing receivable, modified, payment deferral, percentage of related loan balance	5.00%	6.00%	5.00%	5.00%
Weighted-average interest rate, before modification	9.00%	9.00%	9.00%	8.60%
Weighted-average interest rate, after modification	7.30%	7.20%	7.20%	6.90%
Consumer \| Credit card
Financing Receivable, Modifications
Weighted-average interest rate, before modification	23.80%	23.90%	23.80%	23.60%
Weighted-average interest rate, after modification	4.20%	3.90%	4.10%	3.80%

Financing Receivable, Excluding Interest, Modified, Weighted-Average Interest Rate After Modification

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- Definition

Financing Receivable, Excluding Interest, Modified, Weighted-Average Interest Rate Before Modification

+ References

No definition available.

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- Definition

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

+ References

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- Definition

Financing Receivable, Modified, Weighted Average Payment Delay Increase From 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.

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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.

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