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SHARE-BASED PAYMENTS - Narrative (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2015 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock options granted in period (in shares) |  |  | 442,956 | 738,893 | 449,537
Number of options (in shares) | 2,028,847 | 2,122,897 | 1,732,754 | 2,028,847 | 2,045,143
Outstanding options, weighted average exercise price (in dollars per share) | $ 4.48 | $ 6.54 | $ 3.84 | $ 4.48 | $ 5.69
Number of exercises in period (in shares) |  |  | 355,092 | 0 | 8,369
Shares issued for consulting services |  |  | $ 764,000 | $ 370,000 | $ 18,000
Stock Incentive Plan |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Common stock, shares authorized (in shares) |  |  | 9,144,506.6 |  |
Employee Stock Option |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Award vesting period |  |  | 2 years |  |
Award exercise period |  |  | 5 years |  |
Exercisable options, weighted average remaining contractual term |  |  | 3 years 7 months 1 day |  |
Stock options granted in period (in shares) |  |  | 420,000 | 740,000 | 450,000
Number of options (in shares) |  |  | 1,710,000 |  |
Number of exercisable options (in shares) |  |  | 1,440,000 |  |
Options, vested and expected to Vest, aggregate intrinsic value |  |  | $ 414,565 |  |
Restricted Stock Units (RSUs) |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Award vesting period |  |  | 3 years |  |
Number of RSUs granted in period (in shares) |  |  | 1,190,000 | 1,390,000 | 1,210,000
Exercisable options, weighted average exercise price (in dollars per share) |  |  | $ 2.15 |  | $ 2.12
Grants in period, grant date intrinsic value (in dollars per share) | 1,490,000 | $ 1,693,303 |  |  | $ 300,000
Unrecognized compensation costs related to unvested stock options |  |  | $ 50,000 |  |
Unrecognized compensation costs related to RSU awards |  |  | $ 880,000 |  |
Number of exercises in period (in shares) |  |  | 355,092 | 0 | 8,369
Shares issued for consulting services |  |  | $ 760,000 |  | $ 20,000
Exercisable options, intrinsic value |  |  | $ 410,000 |  | $ 10,000
Stock Appreciation Rights (SARs) |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Number of exercises in period (in shares) |  |  | 0 |  |
Maximum | Employee Stock Option |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Exercisable options, weighted average remaining contractual term |  |  | 10 years |  |
Outstanding options, weighted average exercise price (in dollars per share) | $ 4.21 |  |  | $ 4.21 |
Minimum | Employee Stock Option |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Outstanding options, weighted average exercise price (in dollars per share) |  |  | $ 3.85 |  |

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