NET INCOME (LOSS) PER SHARE - Schedule of Calculations of Basic and Diluted Net Income per Share and Potential Common Shares (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Numerator:
Net income (loss)	$ 7,336	$ 36,725	$ (17,472)	$ (29,343)	$ 19,211	$ (3,603)	$ (26,428)	$ (62,504)	$ (2,754)	$ (73,324)	$ 79,812
Denominator:
Denominator for basic net income (loss) per share - weighted average common shares outstanding (in shares)									75,162	78,617	87,425
Dilutive common equivalent shares:
Weighted average restricted stock units (in shares)									0	0	836
Denominator for diluted net income (loss) per share - weighted average shares outstanding (in shares)									75,162	78,617	88,261
Net income (loss) per share:
Basic net income (loss) per share (in dollars per share)									$ (0.04)	$ (0.93)	$ 0.91
Diluted net income (loss) per share (in dollars per share)	$ 0.10	$ 0.49	$ (0.23)	$ (0.38)	$ 0.24	$ (0.05)	$ (0.34)	$ (0.78)	$ (0.04)	$ (0.93)	$ 0.90