EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net (loss) income	$ 918	$ (30,338)	$ (32,296)	$ (28,717)	$ 16,413	$ (7,587)	$ (10,409)	$ 12,200	$ (90,433)	$ 10,617	$ 98,548
Weighted-average common shares outstanding (shares)									79,055	78,564	77,431
Earnings per share, basic (dollars per share)	$ 0.01	$ (0.38)	$ (0.41)	$ (0.37)	$ 0.21	$ (0.10)	$ (0.13)	$ 0.16	$ (1.14)	$ 0.14	$ 1.27
Effective of dilutive securities (shares)									0	4,500	5,401
Weighted - average common shares outstanding, assuming dilution (shares)									79,055	83,064	82,832
Earnings per share, diluted (dollars per share)	$ 0.01	$ (0.38)	$ (0.41)	$ (0.37)	$ 0.20	$ (0.10)	$ (0.13)	$ 0.15	$ (1.14)	$ 0.13	$ 1.19
Outstanding anti-dilutive stock options and RSUs (shares)									5,911	188	221
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average effect of dilutive securities (shares)									0	2,891	3,471
RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average effect of dilutive securities (shares)									0	1,609	1,930