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STOCKHOLDERS' EQUITY - PERFORMANCE BASED STOCK OPTIONS (Details) - shares | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
STOCKHOLDERS' EQUITY |  |  |
Options granted (in shares) | 6,531,931 |  |
Performance-Based Stock Options |  |  |
STOCKHOLDERS' EQUITY |  |  |
Options granted (in shares) |  | 1,000,000 | 4,500,000

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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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Data Type: | xbrli:sharesItemType
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Period Type: | duration

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- Details
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Namespace Prefix: |
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Period Type: |