EARNINGS PER SHARE - Components of Numerator and Denominator for Computation of Basic and Diluted Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Numerator:
Net income attributable to common shareholders - Basic	$ 6,723	$ 14,066	$ 9,563	$ 15,851
Interest on Convertible Notes	0	853	695	2,529
Gain on derivative liability	0	(7,105)	(1,581)	(19,970)
Net income (loss) attributable to common shareholders - Diluted	$ 6,723	$ 7,814	$ 8,677	$ (1,590)
Denominator:
Weighted average common shares - Basic (shares)	35,748,000	32,221,000	34,768,000	32,088,000
Effective of diluted shares:
Share-based awards (shares)	288,000	513,000	444,000	606,000
Convertible Notes (shares)	0	3,521,126	967,342	3,521,126
Weighted average common shares - Diluted (shares)	36,036,000	36,255,000	36,179,000	36,215,000
Net income per share attributable to common shareholders - Basic (in dollars per share)	$ 0.19	$ 0.44	$ 0.28	$ 0.49
Net income (loss) per share attributable to common shareholders - Diluted (in dollars per share)	$ 0.19	$ 0.22	$ 0.24	$ (0.04)