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LOANS AND ALLOWANCE FOR CREDIT LOSSES ON LOANS (Narrative) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2025 | Mar. 31, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Proceeds from the sale of mortgage loans |  |  |  | $ 172,299 | $ 158,867 |
Gain on sale of mortgage loans |  |  |  | (1,977) | (1,535) |
Loans held for sale, at fair value (book value of $9,648 and $10,923, respectively) | $ 9,775 |  |  | $ 9,775 |  | $ 11,049
Other industry exposures |  |  |  | 0 |  |
Non-Accrual Loans | 8,330 |  |  | $ 8,330 |  | 4,829
Loans outstanding | 5,002,927 |  |  | 5,002,927 |  | 4,115,259
Loans and Leases Receivable, Excluded Accrued Interest from Amortized Cost | 16,400 |  |  | 16,400 |  | 12,700
FHLB advances, general debt obligations, pledged collateral | 2,300,000 |  |  | 2,300,000 |  | 1,900,000
Loans And Leases Receivable Impaired Interest Income Foregone | 87 |  | $ 44 | 343 | 148 |
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease) | 7,500 |  |  | 9,800 |  |
Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal) |  |  |  | 9,400 |  |
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Partial Writeoff | 10,700 |  |  | 10,700 |  |
Financing Receivable, Excluding Accrued Interest, 90 Days or More Past Due, Still Accruing | 62 |  | 0 | 62 | 0 |
Recoveries | 109 |  | 141 | 408 | 412 | 623
Residential real estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Proceeds from the sale of mortgage loans | 80,300 |  | 62,400 | 170,300 | 157,300 |
Gain on sale of mortgage loans | (1,000) |  | (687) | (2,000) | (1,500) |
Loans held for sale, at fair value (book value of $9,648 and $10,923, respectively) | 9,600 |  |  | 9,600 |  | 10,900
Unrealized gain (loss) on loans held for sale |  | $ 126 |  | 128 |  |
Non-Accrual Loans | 3,393 |  |  | 3,393 |  | 1,891
Loans outstanding | 2,017,675 |  |  | 2,017,675 |  | 1,752,249
Mortgage Loans in Process of Foreclosure, Amount | 1,100 |  |  | 1,100 |  | 1,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Period Increase (Decrease) | 78 |  | 60 | 2 | (69) |
Recoveries | 8 |  | 6 | 19 | 19 | 26
Commercial real estate - non-owner-occupied |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-Accrual Loans | 127 |  |  | 127 |  | 129
Loans outstanding | 1,771,804 |  |  | 1,771,804 |  | 1,387,252
Recoveries | 0 |  | 1 | 2 | 9 | 10
Commercial |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-Accrual Loans | 4,103 |  |  | 4,103 |  | 1,927
Loans outstanding | 479,461 |  |  | 479,461 |  | 382,785
Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal) | 6,000 |  |  |  |  |
Recoveries | 87 |  | 108 | 317 | 270 | 455
Home equity |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-Accrual Loans | 697 |  |  | 697 |  | 434
Loans outstanding | 313,951 |  |  | 313,951 |  | 253,251
Recoveries | 1 |  | 5 | 1 | 86 | 98
Consumer |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-Accrual Loans | 3 |  |  | 3 |  | 18
Loans outstanding | 18,092 |  |  | 18,092 |  | 15,010
Recoveries | 5 |  | $ 21 | $ 10 | $ 28 | $ 34
Commercial |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Recoveries | $ 1,500 |  |  |  |  |
Non-Residential Building Operators Industry Sector | Loan Concentration Risk | Total Loan Portfolio |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Concentration risk (percentage) |  |  |  | 13.00% |  |
Non-Residential Building Operators Industry Sector | Loan Concentration Risk | Commercial Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Concentration risk (percentage) |  |  |  | 30.00% |  |
Residential Building Operators Industry Sector | Loan Concentration Risk | Total Loan Portfolio |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Concentration risk (percentage) |  |  |  | 12.00% |  |
Residential Building Operators Industry Sector | Loan Concentration Risk | Commercial Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Concentration risk (percentage) |  |  |  | 29.00% |  |

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