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LOANS AND ALLOWANCE FOR LOAN LOSSES - Impaired Loans (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018
Unpaid Principal Balance [Abstract] |  |  |
Unpaid principal balance, total | $ 12,068 |  | $ 8,819
Recorded Investment [Abstract] |  |  |
Recorded investment, total | 11,973 |  | 8,731
Allowance for loan losses allocated | 3,976 |  | 2,189
Average Recorded Investment [Abstract] |  |  |
Average recorded investment, total | 10,353 | $ 13,784 |
Interest Income, Accrual Method [Abstract] |  |  |
Interest income, accrual method, total | 11 | 21 |
Commercial Mortgages | Construction |  |  |
Unpaid Principal Balance [Abstract] |  |  |
With no related allowance, unpaid principal balance | 292 |  | 307
Recorded Investment [Abstract] |  |  |
With no related allowance, recorded investment | 293 |  | 308
Average Recorded Investment [Abstract] |  |  |
With no related allowance, average recorded investment | 301 | 359 |
Interest Income, Accrual Method [Abstract] |  |  |
With no related allowance, interest income, accrual method | 2 | 3 |
Commercial Mortgages | Commercial mortgages, other |  |  |
Unpaid Principal Balance [Abstract] |  |  |
With no related allowance, unpaid principal balance | 3,915 |  | 4,007
With related allowance, Unpaid Principal Balance | 5,141 |  | 1,902
Recorded Investment [Abstract] |  |  |
With no related allowance, recorded investment | 3,843 |  | 3,935
With related allowance, recorded investment | 5,142 |  | 1,903
Allowance for loan losses allocated | 2,228 |  | 446
Average Recorded Investment [Abstract] |  |  |
With no related allowance, average recorded investment | 3,889 | 4,175 |
With related allowance, average recorded investment | 3,523 | 2,797 |
Interest Income, Accrual Method [Abstract] |  |  |
With no related allowance, interest income, accrual method | 5 | 5 |
With related allowance, interest income, accrual method | 0 | 1 |
Residential mortgages |  |  |
Unpaid Principal Balance [Abstract] |  |  |
With no related allowance, unpaid principal balance | 420 |  | 424
Recorded Investment [Abstract] |  |  |
With no related allowance, recorded investment | 392 |  | 402
Average Recorded Investment [Abstract] |  |  |
With no related allowance, average recorded investment | 397 | 426 |
Interest Income, Accrual Method [Abstract] |  |  |
With no related allowance, interest income, accrual method | 2 | 2 |
Consumer Loans | Home equity lines and loans |  |  |
Unpaid Principal Balance [Abstract] |  |  |
With no related allowance, unpaid principal balance | 164 |  | 54
Recorded Investment [Abstract] |  |  |
With no related allowance, recorded investment | 167 |  | 55
Average Recorded Investment [Abstract] |  |  |
With no related allowance, average recorded investment | 111 | 63 |
Interest Income, Accrual Method [Abstract] |  |  |
With no related allowance, interest income, accrual method | 1 | 1 |
Commercial and industrial | Commercial and agricultural |  |  |
Unpaid Principal Balance [Abstract] |  |  |
With no related allowance, unpaid principal balance | 304 |  | 345
With related allowance, Unpaid Principal Balance | 1,832 |  | 1,780
Recorded Investment [Abstract] |  |  |
With no related allowance, recorded investment | 304 |  | 346
With related allowance, recorded investment | 1,832 |  | 1,782
Allowance for loan losses allocated | 1,748 |  | $ 1,743
Average Recorded Investment [Abstract] |  |  |
With no related allowance, average recorded investment | 325 | 820 |
With related allowance, average recorded investment | 1,807 | 5,144 |
Interest Income, Accrual Method [Abstract] |  |  |
With no related allowance, interest income, accrual method | 1 | 9 |
With related allowance, interest income, accrual method | $ 0 | $ 0 |

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