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NET LOSS PER SHARE - Dilutive Securities (Details) - shares | 6 Months Ended
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Jun. 30, 2021 | Jun. 30, 2020
Potentially dilutive securities | 28,291,000 | 27,223,000
Stock option |  |
Common stock purchase warrants | 7,461,000 | 5,842,000
Common stock purchase warrants |  |
Common stock purchase warrants | 20,830,000 | 21,381,000

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- Definition Common stock warrants - equity treatment. + References No definition available. + Details
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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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