Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net loss	$ (18,355)	$ (15,929)	$ (48,293)	$ (35,324)
Other comprehensive loss:
Unrealized loss on available-for-sale securities, net of tax	(213)	(52)	(186)	(52)
Comprehensive loss	$ (18,568)	$ (15,981)	$ (48,479)	$ (35,376)