Note 13 - Debt (Details Textual)		12 Months Ended
	Nov. 22, 2011 USD ($)	Jun. 30, 2017 USD ($)
Line of Credit Facility, Maximum Borrowing Capacity		$ 23,000,000
Line of Credit Facility, Interest Rate During Period		2.61%
Minimum Consolidated Cash and Liquid Investments Pursuant to New Loan and Security Agreement		$ 10,000,000
Line of Credit Facility, Commitment Fee Percentage		0.25%
Long-term Line of Credit		$ 9,900,000
Line of Credit Facility, Current Borrowing Capacity		22,100,000
Line of Credit Facility, Remaining Borrowing Capacity		12,200,000
Standby Letters of Credit [Member]
Long-term Line of Credit		900,000
Term Loan [Member]
Debt Instrument, Face Amount	$ 15,500,000
Debt Instrument, Term	10 years
Debt Instrument, Interest Rate, Stated Percentage	4.50%
Line of Credit Facility, Periodic Payment	$ 160,640
Long-term Line of Credit		$ 7,700,000
Maximum [Member]
Current Funded Debt to EBITDA Ratio		2.25
Annual Capital Expenditures		$ 15,000,000
Minimum [Member]
Debt Service Coverage Rate		1.25
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate		1.50%