Condensed Consolidated Balance Sheets (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	Jan. 31, 2013	Apr. 30, 2012
Accounts receivable, allowance (in Dollars)	$ 30	$ 165
Preferred stock, par value (in Dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	5,000,000	5,000,000
Common stock, par value (in Dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	3,900,410	3,884,012
Common stock, shares outstanding	3,900,410	3,884,012
Treasury shares	33,502