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STOCK-BASED COMPENSATION PLANS - Additional information (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost |  |  |  |  |
Stock options outstanding | 744,000 |  | 744,000 |  |
Exercisable Number of Options | 597,000 |  | 597,000 |  |
Proceeds from Stock Options Exercised | $ 0.1 | $ 0.1 | $ 0.1 | $ 0.3 |
Unrecognized compensation expense related to stock options | $ 3.4 |  | $ 3.4 |  |
Weighted-average period of unrecognized compensation expense related to stock options |  |  | 2 years 4 months 24 days |  |
Restricted Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost |  |  |  |  |
Restricted stock were granted |  |  | 95,000 |  |
2017 Stock Option Plan |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized |  |  |  |  | 5,000,000,000
Number of Shares, Granted | 0 | 0 | 0 | 14,000 |
Stock options outstanding | 412,000 |  | 412,000 |  |
Exercisable Number of Options | 265,000 |  | 265,000 |  |
2017 Stock Option Plan | Management [Member] | Restricted Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost |  |  |  |  |
Restricted stock were granted | 30,000 | 38,000 | 95,000 | 208,000 |

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