Expected Amortization Expenses (Detail) - USD ($) $ in Thousands	Apr. 30, 2017	Apr. 30, 2016
Acquired Finite Lived Intangible Assets
Schedule Of Estimated Future Amortization Expense [Line Items]
2018	$ 1,320
2019	1,232
2020	482
2021	175
2022	175
Thereafter	15
Finite-Lived Intangible Assets, Net	3,399	$ 1,858
Capitalized Software
Schedule Of Estimated Future Amortization Expense [Line Items]
2018	3,123
2019	2,864
2020	2,246
Finite-Lived Intangible Assets, Net	$ 8,233