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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Loan Portfolio (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Mar. 31, 2025 | Dec. 31, 2024 | Jun. 30, 2024 | Mar. 31, 2024 | Dec. 31, 2023
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Composition of loan portfolio [Abstract] |  |  |  |  |  |
Total loans, net of deferred loan fees and costs | $ 2,132,414 |  | $ 2,071,419 |  |  |
Allowance for credit losses | (22,665) | $ (22,522) | (21,388) | $ (21,031) | $ (20,471) | $ (22,517)
Loans, net | 2,109,749 |  | 2,050,031 |  |  |
Commercial Mortgages |  |  |  |  |  |
Composition of loan portfolio [Abstract] |  |  |  |  |  |
Total loans, net of deferred loan fees and costs | 1,297,525 |  | 1,217,004 |  |  |
Allowance for credit losses | (12,714) | (12,089) | (11,214) | (10,530) | (10,367) | (12,026)
Commercial Mortgages | Construction |  |  |  |  |  |
Composition of loan portfolio [Abstract] |  |  |  |  |  |
Total loans, net of deferred loan fees and costs | 98,504 |  | 94,943 |  |  |
Commercial Mortgages | Owner occupied commercial real estate |  |  |  |  |  |
Composition of loan portfolio [Abstract] |  |  |  |  |  |
Total loans, net of deferred loan fees and costs | 161,432 |  | 142,279 |  |  |
Commercial Mortgages | Non-owner occupied commercial real estate |  |  |  |  |  |
Composition of loan portfolio [Abstract] |  |  |  |  |  |
Total loans, net of deferred loan fees and costs | 1,037,589 |  | 979,782 |  |  |
Residential Mortgages |  |  |  |  |  |
Composition of loan portfolio [Abstract] |  |  |  |  |  |
Total loans, net of deferred loan fees and costs | 278,221 |  | 274,979 |  |  |
Allowance for credit losses | (2,597) | (2,473) | (2,259) | (2,106) | (2,062) | (2,194)
Consumer Loans |  |  |  |  |  |
Composition of loan portfolio [Abstract] |  |  |  |  |  |
Total loans, net of deferred loan fees and costs | 262,194 |  | 279,915 |  |  |
Allowance for credit losses | (2,830) | $ (2,807) | (3,395) | $ (3,501) | $ (3,526) | $ (3,242)
Consumer Loans | Home equity lines and loans |  |  |  |  |  |
Composition of loan portfolio [Abstract] |  |  |  |  |  |
Total loans, net of deferred loan fees and costs | 101,505 |  | 93,220 |  |  |
Consumer Loans | Indirect consumer loans |  |  |  |  |  |
Composition of loan portfolio [Abstract] |  |  |  |  |  |
Total loans, net of deferred loan fees and costs | 153,324 |  | 178,118 |  |  |
Consumer Loans | Direct consumer loans |  |  |  |  |  |
Composition of loan portfolio [Abstract] |  |  |  |  |  |
Total loans, net of deferred loan fees and costs | 7,365 |  | 8,577 |  |  |
Commercial and industrial |  |  |  |  |  |
Composition of loan portfolio [Abstract] |  |  |  |  |  |
Total loans, net of deferred loan fees and costs | $ 294,474 |  | $ 299,521 |  |  |

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