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LOANS AND ALLOWANCE FOR LOAN LOSSES - Credit Quality Indicator (Details) - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
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Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | $ 1,562,822 | $ 1,541,498
Not Rated |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 451,610 | 448,787
Pass |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 1,059,362 | 1,036,759
Special Mention |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 26,424 | 26,630
Substandard |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 23,080 | 26,813
Doubtful |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 2,346 | 2,509
Commercial and agricultural: |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 341,994 | 370,252
Commercial and agricultural: | Commercial and industrial |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 341,572 | 369,968
Commercial and agricultural: | Commercial and industrial | Not Rated |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Commercial and agricultural: | Commercial and industrial | Pass |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 332,300 | 360,500
Commercial and agricultural: | Commercial and industrial | Special Mention |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 3,529 | 2,999
Commercial and agricultural: | Commercial and industrial | Substandard |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 4,523 | 5,092
Commercial and agricultural: | Commercial and industrial | Doubtful |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 1,220 | 1,377
Commercial and agricultural: | Agricultural |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 422 | 284
Commercial and agricultural: | Agricultural | Not Rated |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Commercial and agricultural: | Agricultural | Pass |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 422 | 284
Commercial and agricultural: | Agricultural | Special Mention |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Commercial and agricultural: | Agricultural | Substandard |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Commercial and agricultural: | Agricultural | Doubtful |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Commercial mortgages: |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 767,200 | 719,145
Commercial mortgages: | Construction |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 67,968 | 62,164
Commercial mortgages: | Construction | Not Rated |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Commercial mortgages: | Construction | Pass |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 67,209 | 59,885
Commercial mortgages: | Construction | Special Mention |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Commercial mortgages: | Construction | Substandard |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 759 | 2,279
Commercial mortgages: | Construction | Doubtful |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Commercial mortgages: | Commercial mortgages |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 699,232 | 656,981
Commercial mortgages: | Commercial mortgages | Not Rated |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Commercial mortgages: | Commercial mortgages | Pass |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 659,431 | 616,090
Commercial mortgages: | Commercial mortgages | Special Mention |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 22,895 | 23,631
Commercial mortgages: | Commercial mortgages | Substandard |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 15,780 | 16,128
Commercial mortgages: | Commercial mortgages | Doubtful |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 1,126 | 1,132
Residential mortgages |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 247,309 | 240,013
Residential and consumer finance receivable [Abstract] |  |
Residential and consumer loans receivable | 247,310 | 240,013
Residential mortgages | Performing |  |
Residential and consumer finance receivable [Abstract] |  |
Residential and consumer loans receivable | 246,394 | 238,381
Residential mortgages | Non-Performing |  |
Residential and consumer finance receivable [Abstract] |  |
Residential and consumer loans receivable | 916 | 1,632
Residential mortgages | Not Rated |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 246,393 | 238,381
Residential mortgages | Pass |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Residential mortgages | Special Mention |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Residential mortgages | Substandard |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 916 | 1,632
Residential mortgages | Doubtful |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Consumer loans: |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 206,319 | 212,088
Consumer loans: | Home equity lines and loans |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 74,309 | 78,761
Residential and consumer finance receivable [Abstract] |  |
Residential and consumer loans receivable | 74,309 | 78,761
Consumer loans: | Home equity lines and loans | Performing |  |
Residential and consumer finance receivable [Abstract] |  |
Residential and consumer loans receivable | 73,539 | 77,602
Consumer loans: | Home equity lines and loans | Non-Performing |  |
Residential and consumer finance receivable [Abstract] |  |
Residential and consumer loans receivable | 770 | 1,159
Consumer loans: | Home equity lines and loans | Not Rated |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 73,539 | 77,602
Consumer loans: | Home equity lines and loans | Pass |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Consumer loans: | Home equity lines and loans | Special Mention |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Consumer loans: | Home equity lines and loans | Substandard |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 770 | 1,159
Consumer loans: | Home equity lines and loans | Doubtful |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Consumer loans: | Indirect consumer loans |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 120,895 | 120,853
Residential and consumer finance receivable [Abstract] |  |
Residential and consumer loans receivable | 120,894 | 120,853
Consumer loans: | Indirect consumer loans | Performing |  |
Residential and consumer finance receivable [Abstract] |  |
Residential and consumer loans receivable | 120,576 | 120,334
Consumer loans: | Indirect consumer loans | Non-Performing |  |
Residential and consumer finance receivable [Abstract] |  |
Residential and consumer loans receivable | 318 | 519
Consumer loans: | Indirect consumer loans | Not Rated |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 120,577 | 120,334
Consumer loans: | Indirect consumer loans | Pass |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Consumer loans: | Indirect consumer loans | Special Mention |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Consumer loans: | Indirect consumer loans | Substandard |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 318 | 519
Consumer loans: | Indirect consumer loans | Doubtful |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Consumer loans: | Direct consumer loans |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 11,115 | 12,474
Consumer loans: | Direct consumer loans | Not Rated |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 11,101 | 12,470
Consumer loans: | Direct consumer loans | Pass |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Consumer loans: | Direct consumer loans | Special Mention |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Consumer loans: | Direct consumer loans | Substandard |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 14 | 4
Consumer loans: | Direct consumer loans | Doubtful |  |
Finance receivable by credit quality indicator [Abstract] |  |
Total ending loans balance | 0 | 0
Consumer loans: | Other Direct Consumer Loans |  |
Residential and consumer finance receivable [Abstract] |  |
Residential and consumer loans receivable | 11,115 | 12,474
Consumer loans: | Other Direct Consumer Loans | Performing |  |
Residential and consumer finance receivable [Abstract] |  |
Residential and consumer loans receivable | 11,101 | 12,470
Consumer loans: | Other Direct Consumer Loans | Non-Performing |  |
Residential and consumer finance receivable [Abstract] |  |
Residential and consumer loans receivable | $ 14 | $ 4

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