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v3.26.1

Loans and allowance for loan losses - Loan Modification Activities to Borrowers Experiencing Financial Difficulty on Financing Receivables (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2026 | Jun. 30, 2025 | Jun. 30, 2026 | Jun. 30, 2025
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | $ 514,000 | $ 472,000 | $ 977,000 | $ 986,000
Percent of Total Loan Class | 0.36% | 0.35% | 0.68% | 0.73%
Guaranteed by Government-Related Entities |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | $ 48,000 | $ 36,000 | $ 62,000 | $ 70,000
Commercial and industrial |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | $ 116,000 | $ 87,000 | $ 213,000 | $ 223,000
Percent of Total Loan Class | 0.18% | 0.14% | 0.32% | 0.36%
Commercial | Commercial real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | $ 144,000 | $ 319,000 | $ 418,000 | $ 452,000
Percent of Total Loan Class | 0.68% | 1.58% | 1.97% | 2.24%
Residential builder and developer | Commercial real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | $ 0 | $ 0 | $ 9,000 | $ 0
Percent of Total Loan Class | 0.00% | 0.00% | 7.85% | 0.00%
Other commercial construction | Commercial real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | $ 187,000 | $ 12,000 | $ 249,000 | $ 214,000
Percent of Total Loan Class | 5.94% | 27.00% | 7.92% | 5.03%
Residential | Residential real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | $ 58,000 | $ 44,000 | $ 79,000 | $ 87,000
Percent of Total Loan Class | 0.23% | 18.00% | 0.31% | 36.00%
Home equity lines and loans (e) | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | $ 1,000 | $ 0 | $ 1,000 | $ 0
Percent of Total Loan Class | 0.02% | 0.00% | 0.02% | 0.00%
Recreational finance | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | $ 0 | $ 0 | $ 0 | $ 0
Percent of Total Loan Class | 0.00% | 0.00% | 0.00% | 0.00%
Automobile | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | $ 0 | $ 0 | $ 0 | $ 0
Percent of Total Loan Class | 0.00% | 0.00% | 0.00% | 0.00%
Other | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | $ 8,000 | $ 10,000 | $ 8,000 | $ 10,000
Percent of Total Loan Class | 0.32% | 44.00% | 0.32% | 44.00%
Unfunded Loan Commitment |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | $ 29,000 | $ 10,000 | $ 45,000 | $ 18,000
Term Extension |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 423,000 | 393,000 | 764,000 | 824,000
Term Extension | Commercial and industrial |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 73,000 | 68,000 | 136,000 | 130,000
Term Extension | Commercial | Commercial real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 120,000 | 266,000 | 313,000 | 399,000
Term Extension | Residential builder and developer | Commercial real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 0 | 0 | 9,000 | 0
Term Extension | Other commercial construction | Commercial real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 183,000 | 12,000 | 245,000 | 214,000
Term Extension | Residential | Residential real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 39,000 | 37,000 | 53,000 | 71,000
Term Extension | Home equity lines and loans (e) | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 0 | 0 | 0 | 0
Term Extension | Recreational finance | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 0 | 0 | 0 | 0
Term Extension | Automobile | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 0 | 0 | 0 | 0
Term Extension | Other | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 8,000 | 10,000 | 8,000 | 10,000
Other |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 9,000 | 70,000 | 23,000 | 74,000
Other | Commercial and industrial |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 6,000 | 16,000 | 9,000 | 17,000
Other | Commercial | Commercial real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 1,000 | 53,000 | 9,000 | 53,000
Other | Residential builder and developer | Commercial real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 0 | 0 | 0 | 0
Other | Other commercial construction | Commercial real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 0 | 0 | 0 | 0
Other | Residential | Residential real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 2,000 | 1,000 | 5,000 | 4,000
Other | Home equity lines and loans (e) | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 0 | 0 | 0 | 0
Other | Recreational finance | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 0 | 0 | 0 | 0
Other | Automobile | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 0 | 0 | 0 | 0
Other | Other | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 0 | 0 | 0 | 0
Combination of Modification Types |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 82,000 | 9,000 | 190,000 | 88,000
Combination of Modification Types | Commercial and industrial |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 37,000 | 3,000 | 68,000 | 76,000
Combination of Modification Types | Commercial | Commercial real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 23,000 | 0 | 96,000 | 0
Combination of Modification Types | Residential builder and developer | Commercial real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 0 | 0 | 0 | 0
Combination of Modification Types | Other commercial construction | Commercial real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 4,000 | 0 | 4,000 | 0
Combination of Modification Types | Residential | Residential real estate |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 17,000 | 6,000 | 21,000 | 12,000
Combination of Modification Types | Home equity lines and loans (e) | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 1,000 | 0 | 1,000 | 0
Combination of Modification Types | Recreational finance | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 0 | 0 | 0 | 0
Combination of Modification Types | Automobile | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | 0 | 0 | 0 | 0
Combination of Modification Types | Other | Consumer |  |  |  |
Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] |  |  |  |
Modified in period | $ 0 | $ 0 | $ 0 | $ 0

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- Definition Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty. + 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 + Details
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