Consolidated Balance Sheets (Parentheticals) (USD $)	Apr. 30, 2015	Apr. 30, 2014
Preferred stock, par value (in Dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000us-gaap_PreferredStockSharesAuthorized	1,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Preferred stock, shares outstanding	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock, par value (in Dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	50,000,000us-gaap_CommonStockSharesAuthorized	50,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	12,688,890us-gaap_CommonStockSharesIssued	12,452,809us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	8,529,223us-gaap_CommonStockSharesOutstanding	8,735,842us-gaap_CommonStockSharesOutstanding
Treasury stock, shares	4,159,667us-gaap_TreasuryStockShares	3,716,967us-gaap_TreasuryStockShares

Face amount or stated value per share of common stock.

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