EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Earnings Per Share
Net loss	$ (6,951)	$ (22,618)
Weighted average shares outstanding - basic	37,001,977	36,498,482
Weighted average shares outstanding - diluted	37,001,977	36,498,482
Total anti-dilutive shares (in shares)	0	208,510
Basic and diluted:
Basic and diluted loss per share	$ (0.19)	$ (0.62)
Unvested restricted stock units and unexercised options
Earnings Per Share
Total anti-dilutive shares (in shares)	889,093	537,497

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.

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