EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share
Net income (loss)	$ 12,928	$ 1,637	$ (9,690)	$ (16,097)
Weighted average shares outstanding - basic	36,790,401	36,286,528	36,645,248	36,187,340
Effect of potentially dilutive restricted stock units and options	614,000	257,000
Weighted average shares outstanding - diluted	37,404,360	36,543,740	36,645,248	36,187,340
Total anti-dilutive shares (in shares)	54,467	449,602	119,881	312,790
Basic and Diluted:
Basic income (loss) per share (in dollars per share)	$ 0.35	$ 0.05	$ (0.26)	$ (0.44)
Diluted income (loss) per share (in dollars per share)	$ 0.35	$ 0.04	$ (0.26)	$ (0.44)
Unvested restricted stock units and unexercised options
Earnings Per Share
Total anti-dilutive shares (in shares)			669,641	330,195

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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