Stockholders' Equity (Details) $ in Thousands	12 Months Ended
Apr. 30, 2016 USD ($) shares
Treasury Stock
Shares repurchased, cost	$ 5,827
Proceeds from reissuance of treasury stock	4,900
Increase to Retained earnings (accumulated deficit) for difference between cost of treasury stock and proceeds from reissuance	$ 1
Treasury Stock
Treasury Stock
Number of shares repurchased \| shares	395
Shares repurchased, cost	$ 5,827

The cash inflow from the issuance of an equity stock that has been previously reacquired by the entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
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In cases when treasury stock is reissued at a price lower than the cost to repurchase, the excess difference between the selling price and cost to repurchase is charged against retained earnings (assuming that all APIC arising from treasury stock transactions has first been exhausted).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Number of shares that have been repurchased during the period and are being held in treasury.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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