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, 2025	Mar. 31, 2024
Commercial \| Commercial and industrial loans
Financing Receivable, Modifications
Weighted-average length of term extensions	6 months	5 months
Weighted-average length of payment delay	4 months	3 months
Commercial \| Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
Weighted-average length of term extensions	9 months	3 months
Weighted-average length of payment delay	10 months
Commercial \| Commercial mortgage nonowner-occupied loans
Financing Receivable, Modifications
Weighted-average length of term extensions	4 months	6 months
Commercial \| Commercial construction loans
Financing Receivable, Modifications
Weighted-average length of term extensions	13 months
Weighted-average length of payment delay	7 months
Residential Mortgage
Financing Receivable, Modifications
Weighted-average length of term extensions	10 years 1 month 6 days	10 years 10 months 24 days
Approximate amount of payment delays as a percentage of the related loan balances	11.00%	12.00%
Consumer \| Home equity
Financing Receivable, Modifications
Weighted-average length of term extensions	16 years 9 months 18 days	27 years 1 month 6 days
Approximate amount of payment delays as a percentage of the related loan balances	8.00%	4.00%
Weighted-average interest rate, before modification	8.30%	9.10%
Weighted-average interest rate, after modification	6.90%	7.30%
Consumer \| Credit card
Financing Receivable, Modifications
Weighted-average interest rate, before modification	23.00%	24.10%
Weighted-average interest rate, after modification	4.30%	4.20%

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

No definition available.

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- Definition

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

+ References

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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

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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

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