LOSS PER SHARE - Schedule of Earnings Per Share, Basic and Diluted (Detail) - 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
Earnings Per Share [Abstract]
Net loss	$ (37,541)	$ (39,607)	$ (40,493)	$ (34,126)	$ (31,516)	$ (33,191)	$ (35,854)	$ (25,184)	$ (151,767)	$ (125,745)	$ (231,459)
Basic and diluted weighted average common shares outstanding (in shares)	218,819	218,780	218,742	217,838	217,408	217,380	206,531	204,772	218,548	211,574	188,536
Loss per share:
Basic and diluted (in dollars per share)	$ (0.17)	$ (0.18)	$ (0.19)	$ (0.16)	$ (0.14)	$ (0.15)	$ (0.17)	$ (0.12)	$ (0.69)	$ (0.59)	$ (1.23)