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LOANS AND ALLOWANCE FOR LOAN LOSSES - Impaired Loans (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2017 | Mar. 31, 2016 | Dec. 31, 2016
Unpaid Principal Balance [Abstract] |  |  |
Unpaid principal balance, total | $ 14,364 |  | $ 12,852
Recorded Investment [Abstract] |  |  |
Recorded investment, total | 13,440 |  | 11,926
Allowance for loan losses allocated | 998 |  | 876
Average Recorded Investment [Abstract] |  |  |
Average recorded investment, total | 12,684 | $ 14,607 |
Interest Income, Accrual Method [Abstract] |  |  |
Interest income, accrual method, total | 75 | 87 |
Commercial mortgages: | Construction |  |  |
Unpaid Principal Balance [Abstract] |  |  |
With no related allowance, Unpaid Principal Balance | 1,558 |  | 277
Recorded Investment [Abstract] |  |  |
With no related allowance, Recorded Investment | 1,559 |  | 278
Average Recorded Investment [Abstract] |  |  |
With no related allowance, Average Recorded Investment | 919 | 348 |
Interest Income, Accrual Method [Abstract] |  |  |
With no related allowance, Interest Income, Accrual Method | 3 | 4 |
Commercial mortgages: | Commercial mortgages |  |  |
Unpaid Principal Balance [Abstract] |  |  |
With no related allowance, Unpaid Principal Balance | 6,133 |  | 8,792
With related allowance, Unpaid Principal Balance | 5,206 |  | 2,245
Recorded Investment [Abstract] |  |  |
With no related allowance, Recorded Investment | 6,144 |  | 7,857
With related allowance, Recorded Investment | 4,266 |  | 2,247
Allowance for loan losses allocated | 845 |  | 735
Average Recorded Investment [Abstract] |  |  |
With no related allowance, Average Recorded Investment | 7,000 | 7,395 |
With related allowance, Average Recorded Investment | 3,257 | 4,845 |
Interest Income, Accrual Method [Abstract] |  |  |
With no related allowance, Interest Income, Accrual Method | 59 | 68 |
With related allowance, Interest Income, Accrual Method | 1 | 1 |
Residential mortgages |  |  |
Unpaid Principal Balance [Abstract] |  |  |
With no related allowance, Unpaid Principal Balance | 389 |  | 395
Recorded Investment [Abstract] |  |  |
With no related allowance, Recorded Investment | 390 |  | 396
Average Recorded Investment [Abstract] |  |  |
With no related allowance, Average Recorded Investment | 393 | 273 |
Interest Income, Accrual Method [Abstract] |  |  |
With no related allowance, Interest Income, Accrual Method | 2 | 0 |
Consumer Loans | Home equity lines and loans |  |  |
Unpaid Principal Balance [Abstract] |  |  |
With no related allowance, Unpaid Principal Balance | 72 |  | 93
With related allowance, Unpaid Principal Balance | 360 |  | 360
Recorded Investment [Abstract] |  |  |
With no related allowance, Recorded Investment | 72 |  | 95
With related allowance, Recorded Investment | 360 |  | 360
Allowance for loan losses allocated | 153 |  | 141
Average Recorded Investment [Abstract] |  |  |
With no related allowance, Average Recorded Investment | 84 | 107 |
With related allowance, Average Recorded Investment | 360 | 364 |
Interest Income, Accrual Method [Abstract] |  |  |
With no related allowance, Interest Income, Accrual Method | 1 | 1 |
With related allowance, Interest Income, Accrual Method | 0 | 0 |
Commercial and industrial | Commercial and agricultural: |  |  |
Unpaid Principal Balance [Abstract] |  |  |
With no related allowance, Unpaid Principal Balance | 646 |  | 690
Recorded Investment [Abstract] |  |  |
With no related allowance, Recorded Investment | 649 |  | $ 693
Average Recorded Investment [Abstract] |  |  |
With no related allowance, Average Recorded Investment | 671 | 1,266 |
With related allowance, Average Recorded Investment | 0 | 9 |
Interest Income, Accrual Method [Abstract] |  |  |
With no related allowance, Interest Income, Accrual Method | 9 | 13 |
With related allowance, Interest Income, Accrual Method | $ 0 | $ 0 |

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