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Additional Information Pertaining to Stock Options and SARs (Detail) (USD $)
In Thousands, except Per Share data, unless otherwise specified |
12 Months Ended | ||
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Apr. 30, 2013
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Apr. 30, 2012
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Apr. 30, 2011
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| Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | |||
| Weighted-average fair value of stock options granted | $ 9.61 | $ 6.07 | |
| Total fair value of stock options vested | $ 1,001 | $ 1,065 | $ 747 |
| Total intrinsic value of stock options exercised | $ 1,547 | $ 1,485 | $ 5,164 |
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- Definition
The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. 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. No definition available.
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- Details
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