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, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Commercial \| Commercial and industrial loans
Financing Receivable, Modifications
Weighted-average length of term extensions	8 months	5 months	13 months	9 months
Weighted-average length of payment delay		21 months	14 months	13 months
Commercial \| Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
Weighted-average length of term extensions	5 months	6 months	6 months	13 months
Weighted-average length of payment delay	4 months		4 months
Commercial \| Commercial mortgage nonowner-occupied loans
Financing Receivable, Modifications
Weighted-average length of term extensions	5 months	5 months	8 months	7 months
Commercial \| Commercial construction loans
Financing Receivable, Modifications
Weighted-average length of term extensions		5 months	12 months	9 months
Weighted-average length of payment delay	6 months		6 months
Residential Mortgage
Financing Receivable, Modifications
Weighted-average length of term extensions	8 years 10 months 24 days	9 years 7 months 6 days	9 years 7 months 6 days	10 years
Approximate amount of payment delays as a percentage of the related loan balances	11.00%	13.00%	11.00%	12.00%
Weighted-average interest rate, before modification	7.00%	7.50%	7.20%	7.70%
Weighted-average interest rate, after modification	6.60%	6.80%	6.90%	7.00%
Consumer \| Home equity
Financing Receivable, Modifications
Weighted-average length of term extensions	22 years 10 months 24 days	22 years 10 months 24 days	20 years 9 months 18 days	24 years
Approximate amount of payment delays as a percentage of the related loan balances	7.00%	5.00%	7.00%	5.00%
Weighted-average interest rate, before modification	8.60%	9.00%	8.60%	9.00%
Weighted-average interest rate, after modification	6.90%	7.30%	7.00%	7.20%
Consumer \| Credit card
Financing Receivable, Modifications
Weighted-average interest rate, before modification	23.00%	23.80%	23.10%	23.80%
Weighted-average interest rate, after modification	3.90%	4.20%	4.00%	4.10%

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

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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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