Condensed Consolidated Balance Sheets (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	Jul. 31, 2013	Apr. 30, 2013
Accounts receivable, allowance (in Dollars)	$ 57	$ 35
Preferred stock, par value (in Dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in Shares)	5,000,000	5,000,000
Preferred stock, shares issued (in Shares)	0	0
Preferred stock, shares outstanding (in Shares)	0	0
Common stock, par value (in Dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in Shares)	10,000,000	10,000,000
Common stock, shares issued (in Shares)	3,889,368	3,897,832
Common stock, shares outstanding (in Shares)	3,889,368	3,897,832
Treasury shares (in Shares)	75,681	59,414