Consolidated Statements of Shareholders' Equity (Parentheticals) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2012
Payment of dividends per share	$ 0.72	$ 0.66	$ 0.60
Exercise of stock options,shares	140,785	198,200	159,600

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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