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Loans and Allowance for Credit Losses - Age Analysis of Past Due Loans Segregated by Class of Loans (Details) - USD ($) $ in Thousands | Jun. 30, 2026 | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | --- | ---
Financing Receivable, Past Due [Line Items] |  |  |
Total | $ 8,058,386 | $ 8,071,957 |
Nonaccrual | 40,216 | 55,558 | $ 27,937
Current |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 8,004,659 | 8,003,815 |
Total Past Due Loans |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 53,727 | 68,142 |
30-59 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 4,437 | 5,195 |
60-89 Days Past Due |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 9,074 | 7,389 |
Commercial loans | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,784,318 | 2,921,761 |
Nonaccrual | 6,937 | 15,185 | 3,228
Commercial loans | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,408,034 | 1,330,605 |
Nonaccrual | 16,243 | 24,906 | 11,173
Commercial loans | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 466,210 | 365,377 |
Nonaccrual | 0 | 869 | 0
Commercial loans | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,289,133 | 1,315,863 |
Nonaccrual | 5,018 | 3,576 | 2,988
Commercial loans | Current | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,773,080 | 2,906,576 |
Commercial loans | Current | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,391,791 | 1,305,388 |
Commercial loans | Current | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 466,210 | 364,508 |
Commercial loans | Current | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,281,110 | 1,308,368 |
Commercial loans | Total Past Due Loans | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 11,238 | 15,185 |
Commercial loans | Total Past Due Loans | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 16,243 | 25,217 |
Commercial loans | Total Past Due Loans | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 869 |
Commercial loans | Total Past Due Loans | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 8,023 | 7,495 |
Commercial loans | 30-59 Days Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 0 |
Commercial loans | 30-59 Days Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 311 |
Commercial loans | 30-59 Days Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 0 |
Commercial loans | 30-59 Days Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 711 | 999 |
Commercial loans | 60-89 Days Past Due | Commercial real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 4,301 | 0 |
Commercial loans | 60-89 Days Past Due | Commercial and industrial |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 0 |
Commercial loans | 60-89 Days Past Due | Commercial construction |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 0 | 0 |
Commercial loans | 60-89 Days Past Due | Business banking |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,294 | 2,920 |
Consumer loans | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,030,605 | 2,047,071 |
Nonaccrual | 11,878 | 10,864 | 10,318
Consumer loans | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 80,086 | 91,280 |
Nonaccrual | 140 | 158 | $ 230
Consumer loans | Current | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,013,568 | 2,028,472 |
Consumer loans | Current | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 78,900 | 90,503 |
Consumer loans | Total Past Due Loans | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 17,037 | 18,599 |
Consumer loans | Total Past Due Loans | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,186 | 777 |
Consumer loans | 30-59 Days Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,697 | 3,281 |
Consumer loans | 30-59 Days Past Due | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 1,029 | 604 |
Consumer loans | 60-89 Days Past Due | Consumer real estate |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | 2,462 | 4,454 |
Consumer loans | 60-89 Days Past Due | Other consumer |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Total | $ 17 | $ 15 |

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