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LOANS AND ALLOWANCE FOR LOAN LOSSES - Allowances (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019 | Mar. 31, 2020 | Dec. 31, 2019
Allowance for loan losses, by portfolio segment [Roll Forward] |  |  |  |  |
Beginning balance | $ 23,478 | $ 18,944 | $ 18,944 |  |
Charge-offs | (433) | (448) |  |  |
Recoveries | 140 | 156 |  |  |
Net recoveries (charge-offs) | (294) | (292) |  |  |
Provision | 3,050 | 1,093 |  |  |
Ending balance | 26,233 | 19,745 | 23,478 |  |
Ending allowance balance attributable to loans [Abstract] |  |  |  |  |
Individually evaluated for impairment |  |  |  | $ 7,909 | $ 8,097
Collectively evaluated for impairment |  |  |  | 18,324 | 15,381
Total ending allowance balance | 26,233 | 19,745 | 23,478 | 26,233 | 23,478
Loans [Abstract] |  |  |  |  |
Loans individually evaluated for impairment |  |  |  | 15,097 | 15,665
Loans collectively evaluated for impairment |  |  |  | 1,309,123 | 1,297,238
Total recorded investment in loans |  |  |  | 1,324,220 | 1,312,903
Commercial and Agricultural |  |  |  |  |
Allowance for loan losses, by portfolio segment [Roll Forward] |  |  |  |  |
Beginning balance | 10,227 | 5,383 | 5,383 |  |
Charge-offs | (30) | (7) |  |  |
Recoveries | 4 | 11 |  |  |
Net recoveries (charge-offs) | (26) | 4 |  |  |
Provision | 990 | 42 |  |  |
Ending balance | 11,191 | 5,429 | 10,227 |  |
Ending allowance balance attributable to loans [Abstract] |  |  |  |  |
Individually evaluated for impairment |  |  |  | 5,851 | 6,000
Collectively evaluated for impairment |  |  |  | 5,340 | 4,227
Total ending allowance balance | 11,191 | 5,429 | 10,227 | 11,191 | 10,227
Loans [Abstract] |  |  |  |  |
Loans individually evaluated for impairment |  |  |  | 5,952 | 6,147
Loans collectively evaluated for impairment |  |  |  | 230,698 | 224,775
Total recorded investment in loans |  |  |  | 236,650 | 230,922
Commercial Mortgages |  |  |  |  |
Allowance for loan losses, by portfolio segment [Roll Forward] |  |  |  |  |
Beginning balance | 8,869 | 8,184 | 8,184 |  |
Charge-offs | 0 | 0 |  |  |
Recoveries | 1 | 1 |  |  |
Net recoveries (charge-offs) | 0 | 1 |  |  |
Provision | 1,603 | 1,289 |  |  |
Ending balance | 10,472 | 9,474 | 8,869 |  |
Ending allowance balance attributable to loans [Abstract] |  |  |  |  |
Individually evaluated for impairment |  |  |  | 2,058 | 2,097
Collectively evaluated for impairment |  |  |  | 8,414 | 6,772
Total ending allowance balance | 10,472 | 9,474 | 8,869 | 10,472 | 8,869
Loans [Abstract] |  |  |  |  |
Loans individually evaluated for impairment |  |  |  | 8,478 | 8,844
Loans collectively evaluated for impairment |  |  |  | 653,183 | 641,726
Total recorded investment in loans |  |  |  | 661,661 | 650,570
Residential mortgages |  |  |  |  |
Allowance for loan losses, by portfolio segment [Roll Forward] |  |  |  |  |
Beginning balance | 1,252 | 1,226 | 1,226 |  |
Charge-offs | 0 | (2) |  |  |
Recoveries | 0 | 0 |  |  |
Net recoveries (charge-offs) | 0 | (2) |  |  |
Provision | 169 | (9) |  |  |
Ending balance | 1,421 | 1,215 | 1,252 |  |
Ending allowance balance attributable to loans [Abstract] |  |  |  |  |
Individually evaluated for impairment |  |  |  | 0 | 0
Collectively evaluated for impairment |  |  |  | 1,421 | 1,252
Total ending allowance balance | 1,421 | 1,215 | 1,252 | 1,421 | 1,252
Loans [Abstract] |  |  |  |  |
Loans individually evaluated for impairment |  |  |  | 518 | 525
Loans collectively evaluated for impairment |  |  |  | 192,751 | 188,349
Total recorded investment in loans |  |  |  | 193,269 | 188,874
Consumer Loans |  |  |  |  |
Allowance for loan losses, by portfolio segment [Roll Forward] |  |  |  |  |
Beginning balance | 3,130 | 4,151 | 4,151 |  |
Charge-offs | (403) | (439) |  |  |
Recoveries | 135 | 144 |  |  |
Net recoveries (charge-offs) | (268) | (295) |  |  |
Provision | 288 | (229) |  |  |
Ending balance | 3,149 | 3,627 | 3,130 |  |
Ending allowance balance attributable to loans [Abstract] |  |  |  |  |
Individually evaluated for impairment |  |  |  | 0 | 0
Collectively evaluated for impairment |  |  |  | 3,149 | 3,130
Total ending allowance balance | $ 3,149 | $ 3,627 | $ 3,130 | 3,149 | 3,130
Loans [Abstract] |  |  |  |  |
Loans individually evaluated for impairment |  |  |  | 149 | 149
Loans collectively evaluated for impairment |  |  |  | 232,491 | 242,388
Total recorded investment in loans |  |  |  | $ 232,640 | $ 242,537

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