Quarterly report pursuant to Section 13 or 15(d)

Stock Options Transactions (Detail)

v3.3.1.900
Stock Options Transactions (Detail) - Stock Options
$ / shares in Units, shares in Thousands, $ in Thousands
6 Months Ended
Oct. 31, 2015
USD ($)
$ / shares
shares
Options  
Outstanding, April 30, 2015 | shares 202
Exercised | shares (81)
Forfeited/expired. | shares (5)
Outstanding, October 31, 2015 | shares 116
Exercisable, October 31, 2015 | shares 116
Weighted Average Exercise Price  
Outstanding, April 30, 2015 | $ / shares $ 15.45
Exercised | $ / shares 15.26
Forfeited/expired. | $ / shares 17.97
Outstanding, October 31, 2015 | $ / shares 15.53
Exercisable, October 31, 2015 | $ / shares $ 15.53
Weighted-Average Remaining Contractual Life (In Years)  
Outstanding, October 31, 2015 1 year 5 months 16 days
Exercisable, October 31, 2015 1 year 5 months 16 days
Aggregate Intrinsic Value  
Outstanding, October 31, 2015 | $ $ 2,416
Exercisable, October 31, 2015 | $ $ 2,416