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STOCKHOLDERS' EQUITY - EQUITY PLANS - SCHEDULE OF AGGREGATE OPTION AND AWARD ACTIVITY (Parenthetical) (Details) - shares | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Feb. 29, 2020 | Jan. 31, 2019
STOCKHOLDERS' EQUITY |  |  |  |
Options granted (in shares) | 11,735,600 |  |  |
Common stock, shares reserved for future issuance | 45,395,620 |  |  |
2018 Inducement Award Plan |  |  |  |
STOCKHOLDERS' EQUITY |  |  |  |
Common stock, shares reserved for future issuance |  | 3,000,000 |  | 8,000,000
Subsequent Event | 2018 Inducement Award Plan |  |  |  |
STOCKHOLDERS' EQUITY |  |  |  |
Common stock, shares reserved for future issuance |  |  | 9,300,000 |
Performance-Based Stock Options |  |  |  |
STOCKHOLDERS' EQUITY |  |  |  |
Options granted (in shares) | 1,000,000 | 4,500,000 |  |

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- Definition Aggregate number of common shares reserved for future issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + Details
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