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STOCKHOLDERS' EQUITY - STOCK OPTIONS OUTSTANDING (Details) | 12 Months Ended
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Dec. 31, 2017 $ / shares shares
$1.10 - $1.51 |
Exercise Price Range |
Exercise price, low end of range (in dollars per share) | $ 1.10
Exercise price, high end of range (in dollars per share) | $ 1.51
Options Outstanding |
Number of Shares | shares | 5,655,662
Weighted Average Exercise Price Per Share (in dollars per share) | $ 1.45
Weighted Average Remaining Contractual Life (In years) | 4 years 10 months 20 days
$1.55 - $2.16 |
Exercise Price Range |
Exercise price, low end of range (in dollars per share) | $ 1.55
Exercise price, high end of range (in dollars per share) | $ 2.16
Options Outstanding |
Number of Shares | shares | 5,631,031
Weighted Average Exercise Price Per Share (in dollars per share) | $ 2.08
Weighted Average Remaining Contractual Life (In years) | 7 years 14 days
$2.22 - $4.34 |
Exercise Price Range |
Exercise price, low end of range (in dollars per share) | $ 2.22
Exercise price, high end of range (in dollars per share) | $ 4.34
Options Outstanding |
Number of Shares | shares | 6,000,783
Weighted Average Exercise Price Per Share (in dollars per share) | $ 3.37
Weighted Average Remaining Contractual Life (In years) | 7 years 7 months 6 days
$4.42 - $7.31 |
Exercise Price Range |
Exercise price, low end of range (in dollars per share) | $ 4.42
Exercise price, high end of range (in dollars per share) | $ 7.31
Options Outstanding |
Number of Shares | shares | 5,121,053
Weighted Average Exercise Price Per Share (in dollars per share) | $ 5.10
Weighted Average Remaining Contractual Life (In years) | 5 years 3 months 7 days
$1.10 - $7.31 |
Exercise Price Range |
Exercise price, low end of range (in dollars per share) | $ 1.10
Exercise price, high end of range (in dollars per share) | $ 7.31
Options Outstanding |
Number of Shares | shares | 22,408,529
Weighted Average Exercise Price Per Share (in dollars per share) | $ 2.96
Weighted Average Remaining Contractual Life (In years) | 6 years 2 months 26 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The ceiling 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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