Annual report pursuant to Section 13 and 15(d)

Employee Stock Plans (Outstanding Stock Options And SARs) (Detail)

v2.4.0.6
Employee Stock Plans (Outstanding Stock Options And SARs) (Detail) (USD $)
In Thousands, except Per Share data, unless otherwise specified
 12 Months Ended
Apr. 30, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Options Outstanding, Shares 1,100
Options Outstanding, Weighted-Average Remaining Contractual Life (in years) 2 years 6 months
Options Outstanding, Weighted-Average Exercise Price $ 14.72
Options Exercisable, Shares 864
Options Exercisable, Weighted-Average Remaining Contractual Life (in years) 2 years 1 month 6 days
Options Exercisable, Weighted-Average Exercise Price $ 15.01
$7.76 - $9.75
  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Range of Exercise Prices, Minimum $ 7.76
Range of Exercise Prices, Maximum $ 9.75
Options Outstanding, Shares 361
Options Outstanding, Weighted-Average Remaining Contractual Life (in years) 2 years 1 month 6 days
Options Outstanding, Weighted-Average Exercise Price $ 9.19
Options Exercisable, Shares 281
Options Exercisable, Weighted-Average Remaining Contractual Life (in years) 1 year 9 months 18 days
Options Exercisable, Weighted-Average Exercise Price $ 9.03
$9.76 - $14.93
  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Range of Exercise Prices, Minimum $ 9.76
Range of Exercise Prices, Maximum $ 14.93
Options Outstanding, Shares 238
Options Outstanding, Weighted-Average Remaining Contractual Life (in years) 3 years 10 months 24 days
Options Outstanding, Weighted-Average Exercise Price $ 13.94
Options Exercisable, Shares 120
Options Exercisable, Weighted-Average Remaining Contractual Life (in years) 3 years 9 months 18 days
Options Exercisable, Weighted-Average Exercise Price $ 14.06
14.94 - $19.25
  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Range of Exercise Prices, Minimum $ 14.94
Range of Exercise Prices, Maximum $ 19.25
Options Outstanding, Shares 239
Options Outstanding, Weighted-Average Remaining Contractual Life (in years) 2 years 1 month 6 days
Options Outstanding, Weighted-Average Exercise Price $ 17.81
Options Exercisable, Shares 231
Options Exercisable, Weighted-Average Remaining Contractual Life (in years) 2 years 1 month 6 days
Options Exercisable, Weighted-Average Exercise Price $ 17.84
$19.26 - $24.08
  
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]  
Range of Exercise Prices, Minimum $ 19.26
Range of Exercise Prices, Maximum $ 24.08
Options Outstanding, Shares 262
Options Outstanding, Weighted-Average Remaining Contractual Life (in years) 2 years 1 month 6 days
Options Outstanding, Weighted-Average Exercise Price $ 20.24
Options Exercisable, Shares 232
Options Exercisable, Weighted-Average Remaining Contractual Life (in years) 1 year 8 months 12 days
Options Exercisable, Weighted-Average Exercise Price $ 19.92