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STOCKHOLDERS' EQUITY - STOCK OPTIONS OUTSTANDING (Details) - $ / shares | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Options Outstanding |  |
Options granted (in shares) | 11,735,600 |
Performance-Based Stock Options |  |
Options Outstanding |  |
Options granted (in shares) | 1,000,000 | 4,500,000
$1.03 - $1.48 |  |
Exercise Price Range |  |
Exercise price, low end of range (in dollars per share) | $ 1.03 |
Exercise price, high end of range (in dollars per share) | $ 1.48 |
Options Outstanding |  |
Number of Shares | 9,578,200 |
Weighted Average Exercise Price Per Share (in dollars per share) | $ 1.19 |
Weighted Average Remaining Contractual Life (In years) | 8 years 3 months 3 days |
$1.50 - $1.74 |  |
Exercise Price Range |  |
Exercise price, low end of range (in dollars per share) | $ 1.50 |
Exercise price, high end of range (in dollars per share) | $ 1.74 |
Options Outstanding |  |
Number of Shares | 10,928,400 |
Weighted Average Exercise Price Per Share (in dollars per share) | $ 1.67 |
Weighted Average Remaining Contractual Life (In years) | 7 years 2 months 1 day |
$1.77 - $2.54 |  |
Exercise Price Range |  |
Exercise price, low end of range (in dollars per share) | $ 1.77 |
Exercise price, high end of range (in dollars per share) | $ 2.54 |
Options Outstanding |  |
Number of Shares | 9,732,417 |
Weighted Average Exercise Price Per Share (in dollars per share) | $ 2.27 |
Weighted Average Remaining Contractual Life (In years) | 6 years 10 months 9 days |
$2.63 - $5.29 |  |
Exercise Price Range |  |
Exercise price, low end of range (in dollars per share) | $ 2.63 |
Exercise price, high end of range (in dollars per share) | $ 5.29 |
Options Outstanding |  |
Number of Shares | 7,374,996 |
Weighted Average Exercise Price Per Share (in dollars per share) | $ 4.54 |
Weighted Average Remaining Contractual Life (In years) | 4 years 5 months 4 days |
$1.03 - $5.29 |  |
Exercise Price Range |  |
Exercise price, low end of range (in dollars per share) | $ 1.03 |
Exercise price, high end of range (in dollars per share) | $ 5.29 |
Options Outstanding |  |
Number of Shares | 37,614,013 |
Weighted Average Exercise Price Per Share (in dollars per share) | $ 2.26 |
Weighted Average Remaining Contractual Life (In years) | 6 years 9 months 29 days |

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- Definition The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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