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v3.26.1

Loans and allowance for loan losses - Effect of Loan Modification on Weighted-average Remaining Life (Detail) | 3 Months Ended | 6 Months Ended
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Jun. 30, 2026 | Jun. 30, 2025 | Jun. 30, 2026 | Jun. 30, 2025
Commercial and industrial |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Weighted-average remaining term | 1 year 1 month 6 days | 7 months 6 days | 1 year 8 months 12 days | 9 months 18 days
Commercial real estate |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Weighted-average remaining term | 1 year 4 months 24 days | 9 months 18 days | 1 year 3 months 18 days | 9 months 18 days
Residential real estate |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Weighted-average remaining term | 10 years 7 months 6 days | 9 years 2 months 12 days | 10 years 9 months 18 days | 9 years 8 months 12 days

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