Property and Equipment and Capitalized Internal-Use Software Development Costs - Property and Equipment, Including Capitalized Software Development Costs (Details) - USD ($) $ in Thousands	Apr. 30, 2016	Apr. 30, 2015
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 63,474	$ 44,858
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(31,825)	(25,804)
Property, Plant and Equipment, Net	31,649	19,054
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	3,207	3,052
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	3,801	1,888
Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	3,170	2,072
Computer Software, Intangible Asset [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	963	962
Software Development [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	39,571	29,628
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 12,762	$ 7,256