Property and Equipment and Capitalized Internal-Use Software Development Costs - Property and Equipment, Including Capitalized Software Development Costs (Details) - USD ($) $ in Thousands	Apr. 30, 2017	Apr. 30, 2016
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 72,057	$ 63,474
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(43,699)	(31,825)
Property, Plant and Equipment, Net	28,358	31,649
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	3,691	3,207
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	3,657	3,801
Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	3,119	3,170
Computer Software, Intangible Asset [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	963	963
Software Development [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	47,574	39,571
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 13,053	$ 12,762