SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Net Loss per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2019 |
Sep. 30, 2019 |
Jun. 30, 2019 |
Mar. 31, 2019 |
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
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| EPS Numerator: | |||||||||||
| Net loss | $ (17,200) | $ (11,490) | $ (20,606) | $ (17,598) | $ 3,228 | $ (23,766) | $ (25,557) | $ (24,385) | $ (66,894) | $ (70,480) | $ (77,992) |
| EPS Denominator - Basic and Diluted: | |||||||||||
| Weighted-average common shares outstanding | 167,400 | 160,529 | 126,324 | ||||||||
| Net loss per common share: | |||||||||||
| Basic and diluted (in dollars per share) | $ (0.10) | $ (0.07) | $ (0.12) | $ (0.11) | $ 0.02 | $ (0.14) | $ (0.16) | $ (0.17) | $ (0.40) | $ (0.44) | $ (0.62) |
| Weighted Average | |||||||||||
| Net loss per common share: | |||||||||||
| Weighted average exercise price of options (in dollars per share) | $ 3.51 | $ 4.20 | $ 3.51 | $ 4.20 | $ 5.45 | ||||||
| Employee stock option | |||||||||||
| Net loss per common share: | |||||||||||
| Antidilutive securities excluded from computation of earnings per share (in shares) | 22,671 | 20,713 | 20,408 | ||||||||
| X | ||||||||||
- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS). No definition available.
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- References No definition available.
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