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Loans and Allowance for Credit Losses - Loans on Nonaccrual Status and Loans Past Due 90 Days or More and Still Accruing (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2025 | Dec. 31, 2024
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | $ 27,937 | $ 22,947
End of Period Nonaccrual | 49,618 | 27,937
Nonaccrual With No Related Allowance | 19,678 | 1,295
Interest income recognized on nonaccrual | 824 | 1,389
Commercial loans | Commercial real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 3,228 | 6,320
End of Period Nonaccrual | 25,648 | 3,228
Nonaccrual With No Related Allowance | 10,814 | 984
Interest income recognized on nonaccrual | 92 | 116
Commercial loans | Commercial and industrial |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 11,173 | 878
End of Period Nonaccrual | 8,979 | 11,173
Nonaccrual With No Related Allowance | 8,864 | 311
Interest income recognized on nonaccrual | 115 | 85
Commercial loans | Commercial construction |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 0 | 4,960
End of Period Nonaccrual | 869 | 0
Nonaccrual With No Related Allowance | 0 | 0
Interest income recognized on nonaccrual | 25 | 700
Commercial loans | Business banking |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 2,988 | 4,147
End of Period Nonaccrual | 4,146 | 2,988
Nonaccrual With No Related Allowance | 0 | 0
Interest income recognized on nonaccrual | 146 | 93
Consumer loans | Consumer real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 10,318 | 6,312
End of Period Nonaccrual | 9,812 | 10,318
Nonaccrual With No Related Allowance | 0 | 0
Interest income recognized on nonaccrual | 443 | 392
Consumer loans | Other consumer |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 230 | 330
End of Period Nonaccrual | 164 | 230
Nonaccrual With No Related Allowance | 0 | 0
Interest income recognized on nonaccrual | $ 3 | $ 3

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