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INVESTMENTS (Details) $ / shares in Units, $ in Thousands |  | 12 Months Ended
--- | --- | ---
Jun. 23, 2021 USD ($) project $ / shares shares | Dec. 31, 2020 USD ($)
Investments |  |
Number of common shares | shares | 4,963,455 |
Warrants received | shares | 2,481,727 |
Proceeds from sale of investments |  | $ 1,266
Disposal Group | Projects in Nevada |  |
Investments |  |
Cash consideration received | $ 500 |
Price per common share for each warrant | $ / shares | $ 0.60 |
Disposal Group | Projects in Nevada, Limousine Butte and Cedar Wash |  |
Investments |  |
Number of projects sold | project | 2 |
Marketable equity securities |  |
Investments |  |
Proceeds from sale of investments |  | $ 1,300

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