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STOCK COMPENSATION (Details) - USD ($) $ / shares in Units, $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
Jan. 31, 2018 | Jan. 31, 2017 | Jan. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Restricted Stock |  |  |  |  |  |
Shares [Roll Forward] |  |  |  |  |  |
Nonvested, beginning of period (in shares) | 25,522 | 23,794 |  | 23,794 |  |
Granted (in shares) |  |  |  | 10,161 |  |
Vested (in shares) |  |  |  | (7,294) |  |
Forfeited or cancelled (in shares) |  |  |  | (1,139) |  |
Nonvested, end of period (in shares) |  |  |  | 25,522 | 23,794 |
Weighted-Average Grant Date Fair Value [Roll Forward] |  |  |  |  |  |
Nonvested, beginning of period (in dollars per share) | $ 38.01 | $ 29.90 |  | $ 29.90 |  |
Granted (in dollars per share) |  |  |  | 49.74 |  |
Vested (in dollars per share) |  |  |  | 29.15 |  |
Forfeitures or cancelled (in dollars per share) |  |  |  | 29.97 |  |
Nonvested, end of period (in dollars per share) |  |  |  | $ 38.01 | $ 29.90 |
Total unrecognized compensation cost related to nonvested shares granted under the Plan |  |  |  | $ 955 |  |
Weighted-average period for recognition |  |  |  | 4 years 22 days |  |
Total fair value of shares vested |  |  |  | $ 382 | $ 193 | $ 314
President and Chief Executive Officer |  |  |  |  |  |
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |  |  |  |
Service period |  |  |  | 12 months |  |
Directors and President and Chief Executive Officer |  |  |  |  |  |
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |  |  |  |
Number of treasury shares reissued to fund stock compensation (in shares) |  | 7,880 | 9,532 |  |  |
Expense related to stock compensation recognized |  |  |  | $ 301 | $ 269 | $ 262
Subsequent Event | Directors and President and Chief Executive Officer |  |  |  |  |  |
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items] |  |  |  |  |  |
Number of treasury shares reissued to fund stock compensation (in shares) | 6,015 |  |  |  |  |

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