EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share
Net income (loss)	$ 4,369	$ (4,161)	$ (5,321)	$ (20,258)
Weighted average shares outstanding - basic	36,856,881	36,340,089	36,716,568	36,238,816
Effect of potentially dilutive restricted stock units and options	700,000
Weighted average shares outstanding - diluted	37,556,594	36,340,089	36,716,568	36,238,816
Total anti-dilutive shares (in shares)	0	867,930	48,502	475,905
Basic and Diluted:
Basic income (loss) per share (in dollars per share)	$ 0.12	$ (0.11)	$ (0.14)	$ (0.56)
Diluted income (loss) per share (in dollars per share)	$ 0.12	$ (0.11)	$ (0.14)	$ (0.56)
Unvested restricted stock units and unexercised options
Earnings Per Share
Total anti-dilutive shares (in shares)		224,663	680,444	295,089

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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