Quarterly report pursuant to Section 13 or 15(d)

Additional Information Pertaining to Stock Options (Detail)

v3.2.0.727
Additional Information Pertaining to Stock Options (Detail) - USD ($)
$ in Thousands
3 Months Ended
Jul. 31, 2015
Jul. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Total fair value of stock options vested $ 96 $ 324
Total intrinsic value of stock options exercised $ 1,360 $ 1,039