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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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Gross number of share options (or share units) granted during the period.

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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.

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Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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