Stock Options Transactions (Detail) - Stock Options - $ / shares shares in Thousands	12 Months Ended
Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2014
Options
Outstanding, beginning of year	202	396	1,100
Exercised	(87)	(179)	(655)
Forfeited/expired	(10)	(15)	(49)
Outstanding, end of year	105	202	396
Exercisable, end of year	105	192	337
Weighted Average Exercise Price
Outstanding, beginning of year	$ 15.45	$ 16.23	$ 14.72
Exercised	15.83	16.99	13.88
Forfeited/expired	18.05	17.72	13.42
Outstanding, end of year	15.01	15.45	16.23
Exercisable, end of year	$ 15.01	$ 15.07	$ 16.11

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.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
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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.

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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.

+ References

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Number of share options (or share units) exercised during the current period.

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