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STOCK BASED COMPENSATION: (Details Textual) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended | 36 Months Ended |
--- | --- | --- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2013 | Feb. 05, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Vesting period |  |  |  | 3 years |  |  |
Share-based Payment Arrangement, Expensed and Capitalized, Amount | $ 799 | $ 745 | $ 700 |  |  |  |
Stock Incentive Plan 2011 |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Common Stock, Capital Shares Reserved for Future Issuance (in shares) |  |  |  |  |  |  | 700,000
Granted (shares) |  |  |  |  |  | 186,072 |
Number of additional shares authorized (shares) |  |  |  | 513,928 |  |  |
Restricted Stock |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Granted (shares) |  |  |  | 19,783,000 | 17,220,000 |  |
Vesting period |  |  |  | 3 years |  |  |
Total compensation cost not yet recognized, stock options |  |  |  | $ 822 | $ 674 |  |
Total compensation cost not yet recognized, period for recognition |  |  |  | 1 year 6 months |  |  |
Options, vested in period, fair value |  |  |  | $ 800 | $ 732 |  |
Restricted Stock | First Anniversary |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Purchase price of common stock (percent) |  |  |  | 33.00% |  |  |
Restricted Stock | Second Anniversary |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Purchase price of common stock (percent) |  |  |  | 33.00% |  |  |
Restricted Stock | Third Anniversary |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Purchase price of common stock (percent) |  |  |  | 34.00% |  |  |

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