Additional Information Pertaining to Stock Options (Detail) - USD ($) $ in Thousands |
3 Months Ended | |
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Jul. 31, 2015 |
Jul. 31, 2014 |
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| 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 |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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