Note 7 - Pledged Assets, Notes Payable and Long-Term Debt (Details) (USD $)				3 Months Ended
	Jul. 31, 2013	Apr. 30, 2013	Jul. 31, 2013 Line of Credit [Member] Prime Rate [Member]	Jul. 31, 2013 Line of Credit [Member]
Note 7 - Pledged Assets, Notes Payable and Long-Term Debt (Details) [Line Items]
Number Of Credit Agreements	2
Line of Credit Facility, Maximum Borrowing Capacity (in Dollars)	$ 6,000,000	$ 6,000,000
Line of Credit Facility, Remaining Borrowing Capacity (in Dollars)	$ 4,587,000
Debt Instrument, Interest Rate, Reference Rate			3.25%
Debt Instrument, Basis Spread on Variable Rate				0.50%
Line of Credit Facility, Interest Rate at Period End	2.75%			2.75%