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LOANS AND ALLOWANCE FOR LOAN LOSSES - Impaired Loans (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Unpaid Principal Balance [Abstract] |  |  |
Unpaid principal balance, total | $ 15,143 |  | $ 15,712
Recorded Investment [Abstract] |  |  |
Recorded investment, total | 15,097 |  | 15,665
Allowance for loan losses allocated | 7,909 |  | 8,097
Average Recorded Investment [Abstract] |  |  |
Average recorded investment, total | 15,381 | $ 10,353 |
Interest Income, Accrual Method [Abstract] |  |  |
Interest income, accrual method, total | 9 | 11 |
Commercial Mortgages | Construction |  |  |
Unpaid Principal Balance [Abstract] |  |  |
With no related allowance, unpaid principal balance | 231 |  | 247
Recorded Investment [Abstract] |  |  |
With no related allowance, recorded investment | 232 |  | 247
Average Recorded Investment [Abstract] |  |  |
With no related allowance, average recorded investment | 239 | 301 |
Interest Income, Accrual Method [Abstract] |  |  |
With no related allowance, interest income, accrual method | 2 | 2 |
Commercial Mortgages | Commercial mortgages, other |  |  |
Unpaid Principal Balance [Abstract] |  |  |
With no related allowance, unpaid principal balance | 3,219 |  | 3,501
With related allowance, Unpaid Principal Balance | 5,025 |  | 5,093
Recorded Investment [Abstract] |  |  |
With no related allowance, recorded investment | 3,220 |  | 3,503
With related allowance, recorded investment | 5,026 |  | 5,094
Allowance for loan losses allocated | 2,058 |  | 2,097
Average Recorded Investment [Abstract] |  |  |
With no related allowance, average recorded investment | 3,362 | 3,889 |
With related allowance, average recorded investment | 5,060 | 3,523 |
Interest Income, Accrual Method [Abstract] |  |  |
With no related allowance, interest income, accrual method | 0 | 5 |
With related allowance, interest income, accrual method | 0 | 0 |
Residential mortgages |  |  |
Unpaid Principal Balance [Abstract] |  |  |
With no related allowance, unpaid principal balance | 547 |  | 554
Recorded Investment [Abstract] |  |  |
With no related allowance, recorded investment | 518 |  | 525
Average Recorded Investment [Abstract] |  |  |
With no related allowance, average recorded investment | 521 | 397 |
Interest Income, Accrual Method [Abstract] |  |  |
With no related allowance, interest income, accrual method | 5 | 2 |
Consumer Loans | Home equity lines and loans |  |  |
Unpaid Principal Balance [Abstract] |  |  |
With no related allowance, unpaid principal balance | 171 |  | 171
Recorded Investment [Abstract] |  |  |
With no related allowance, recorded investment | 149 |  | 149
Average Recorded Investment [Abstract] |  |  |
With no related allowance, average recorded investment | 149 | 111 |
Interest Income, Accrual Method [Abstract] |  |  |
With no related allowance, interest income, accrual method | 2 | 1 |
Commercial and industrial | Commercial and agricultural |  |  |
Unpaid Principal Balance [Abstract] |  |  |
With no related allowance, unpaid principal balance | 105 |  | 133
With related allowance, Unpaid Principal Balance | 5,845 |  | 6,013
Recorded Investment [Abstract] |  |  |
With no related allowance, recorded investment | 106 |  | 133
With related allowance, recorded investment | 5,846 |  | 6,014
Allowance for loan losses allocated | 5,851 |  | $ 6,000
Average Recorded Investment [Abstract] |  |  |
With no related allowance, average recorded investment | 120 | 325 |
With related allowance, average recorded investment | 5,930 | 1,807 |
Interest Income, Accrual Method [Abstract] |  |  |
With no related allowance, interest income, accrual method | 0 | 1 |
With related allowance, interest income, accrual method | $ 0 | $ 0 |

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