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Stock Options and SAR Transactions (Detail) (Stock Options, USD $)
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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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Stock Options
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| Options | |||
| Outstanding, beginning of year | 1,492,000 | 1,833,000 | 2,723,000 |
| Granted | 48,000 | 211,000 | |
| Exercised | (238,000) | (235,000) | (625,000) |
| Forfeited/expired | (154,000) | (154,000) | (476,000) |
| Outstanding, end of year | 1,100,000 | 1,492,000 | 1,833,000 |
| Exercisable, end of year | 864,000 | 1,061,000 | 1,219,000 |
| Weighted Average Exercise Price | |||
| Outstanding, beginning of year | $ 14.00 | $ 13.78 | $ 14.72 |
| Granted | $ 22.71 | $ 13.97 | |
| Exercised | $ 9.32 | $ 12.76 | $ 12.81 |
| Forfeited/expired | $ 16.87 | $ 15.63 | $ 20.55 |
| Outstanding, end of year | $ 14.72 | $ 14.00 | $ 13.78 |
| Exercisable, end of year | $ 15.01 | $ 14.33 | $ 14.64 |
| X | ||||||||||
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- Definition
The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Net number of share options (or share units) granted during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
Weighted average price at which option holders acquired shares when converting their stock options into shares. No definition available.
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- Definition
Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated. No definition available.
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- Definition
Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded. No definition available.
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- Definition
Number of share options (or share units) exercised during the current period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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