NET INCOME (LOSS) PER SHARE - Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Abstract]
Net income (loss)	$ (52,402)	$ (299)	$ (11,227)	$ (10,755)	$ 12,905	$ 6,931	$ 1,248	$ (4,324)	$ (74,683)	$ 16,760	$ (21,474)
Weighted average shares:
Basic									262,730	254,665	247,024
Dilutive shares from stock plans									0	5,362	0
Diluted									262,730	260,027	247,024
Basic net income (loss) per share					$ 0.05	$ 0.03	$ 0.00	$ (0.02)	$ (0.28)	$ 0.07	$ (0.09)
Diluted net income (loss) per share					$ 0.04	$ 0.03	$ 0.00	$ (0.02)	$ (0.28)	$ 0.06	$ (0.09)