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CAPITAL STOCK - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 12 Months Ended |
--- | --- | --- | ---
Feb. 20, 2020 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Mar. 14, 2019
Class of Warrant or Right [Line Items] |  |  |  |  |
Number of warrants outstanding (in shares) |  |  |  |  | 2,328,925
At The Market Sale Of Stock |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |
Sale of Stock, Number of Shares Issued in Transaction |  | 21,361,784 | 8,043,365 | 14,283,254 |
Sale of stock consideration received |  | $ 37,250 | $ 19,680 | $ 31,520 |
Public Offerings |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |
Sale of Stock, Number of Shares Issued in Transaction |  | 19,891,709 | 3,199,866 | 7,576,288 |
Public Offering |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |
Sale of Stock, Price Per Share | $ 1.47 |  |  |  |
Sale of stock consideration received | $ 15,140 |  |  |  |

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