Income Taxes - Income Tax Expense (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Apr. 30, 2016	Jan. 31, 2016	Oct. 31, 2015	Jul. 31, 2015	Apr. 30, 2015	Jan. 31, 2015	Oct. 31, 2014	Jul. 31, 2014	Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2014
Current:
Federal									$ 0	$ (38)	$ 0
State									(77)	182	294
International									556	951	567
Total									479	1,095	861
Deferred:
Federal									(6,635)	(12,491)	(13,930)
State									(1,070)	(2,308)	(2,091)
International									(94)	44	203
Total									(7,799)	(14,755)	(15,818)
Change in valuation allowance									7,358	13,714	14,457
Provision for (benefit from) income taxes	$ 165	$ (163)	$ 124	$ (88)	$ (540)	$ 324	$ 258	$ 12	$ 38	$ 54	$ (500)