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STOCK-BASED COMPENSATION PLANS - Additional information (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | 1,153 |  | 1,153 |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number | 593 |  | 593 |
Weighted Average Exercise Price, Granted |  |  | $ 10.15 | $ 4.53
Proceeds from Stock Options Exercised | $ 0.1 | $ 0.1 | $ 0.3 | $ 0.1
Unrecognized compensation expense related to stock options | $ 3.9 |  | $ 3.9 |
Weighted-average period of unrecognized compensation expense related to stock options |  |  | 2 years 4 months 24 days |
Weighted-average grant date fair value of options granted (in dollars per share) | $ 8.88 |  |  | $ 4.01
Restricted Stock [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  | 208 | 10,000
2017 Stock Option Plan |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | 709 |  | 709 |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number | 164 |  | 164 |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 5,000,000 |  | 5,000,000 |
Number of Warrants, Granted | 0 | 35,000 | 14,000 | 400
2017 Stock Option Plan | Employee Stock Option [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost |  |  |  |
Number of Warrants, Granted |  |  | 14,000 | 415,000
2017 Stock Option Plan | Restricted Stock [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | 38,000 |  | 208,000 |
2017 Stock Option Plan | Management [Member] | Restricted Stock [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | 38,000 | 5,000 | 208,000 | 10,000

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