NET INCOME (LOSS) PER COMMON SHARE - Basic and Diluted Net Income (loss) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Basic Income (Loss) Per Share
Net income (loss)	$ 1,426	$ (21,648)	$ (53,811)	$ (9,138)	$ (20,221)	$ (62,949)
Basic weighted average shares outstanding (in shares)	135,808,435		134,804,963		135,784,286	134,785,749
Net income (loss) per share - Basic (in dollars per share)	$ 0.01		$ (0.40)		$ (0.15)	$ (0.47)
Diluted Income (Loss) Per Share
Net income (loss)	$ 1,426	$ (21,648)	$ (53,811)	$ (9,138)	$ (20,221)	$ (62,949)
Basic weighted average shares outstanding (in shares)	135,808,435		134,804,963		135,784,286	134,785,749
Effect of RSUs and options under the treasury stock method (in shares)	1,979,000		0		0	0
Diluted weighted average shares outstanding (in shares)	137,786,768		134,804,963		135,784,286	134,785,749
Net income (loss) per share - Diluted (in dollars per share)	$ 0.01		$ (0.40)		$ (0.15)	$ (0.47)