STOCK-BASED COMPENSATION - Additional Information (Details) - $ / shares |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
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| Share-based Compensation, Allocation and Classification in Financial Statements [Abstract] | ||||
| Weighted-average Exercise price | $ 6.86 | $ 16.27 | $ 6.84 | $ 14.38 |
| Weighted-average Grant date fair value | $ 5.39 | $ 12.87 | $ 5.37 | $ 11.36 |
| Stock Options | ||||
| Share-based Compensation, Allocation and Classification in Financial Statements [Abstract] | ||||
| Options granted | 1,183,890 | 224,800 | 1,384,890 | 869,800 |
| X | ||||||||||
- Definition Agreed-upon share price for the exchange of the underlying asset relating to the share-based payment award. No definition available.
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- References No definition available.
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| X | ||||||||||
- Definition Gross number of share options (or share units) granted during the period. No definition available.
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| X | ||||||||||
- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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