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SHAREHOLDERS' EQUITY - Stock Options (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2021 | Sep. 30, 2020 | Apr. 16, 2021
STOCK BASED COMPENSATION |  |  |  |
Number of common stock reserved for issuance | 30,000,000.0 | 30,000,000.0 |  | 12,500,000
Shares |  |  |  |
Shares of common stock issued upon exercise of stock options |  | 0 | 60,000 |
Weighted Average Exercise Price |  |  |  |
Weighted average exercise price of stock options (in dollars per share) |  |  | $ 1.06 |
Proceeds from exercise of stock options |  |  | $ 0.1 |
Maximum [Member] |  |  |  |
STOCK BASED COMPENSATION |  |  |  |
Maximum number of shares that may be subject to grants of options to an individual in a calendar year |  | 500,000 |  |
Employees and Directors [Member] |  |  |  |
STOCK BASED COMPENSATION |  |  |  |
Stock options granted (in shares) | 850,000 |  |  |
Exercise price of options granted (in dollars per share) | $ 1.21 |  |  |
Shares |  |  |  |
Granted (in shares) | 850,000 |  |  |
Balance at the end of the period (in shares) | 6,460,050 | 6,460,050 | 8,808,001 |
Weighted Average Exercise Price |  |  |  |
Granted (in dollars per share) | $ 1.21 |  |  |
Granted (in shares) | 850,000 |  |  |
Common Stock [Member] |  |  |  |
Shares |  |  |  |
Shares of common stock issued upon exercise of stock options |  |  | 60,000 |

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