Note 9 - Restructuring Cost (Details Textual) - USD ($)	1 Months Ended	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Restructuring Charges, Total	$ 1,600,000	$ 1,580,000
Restructuring and Related Cost, Expected Cost Remaining	2,400,000	2,400,000
Restructuring Reserve, Ending Balance	1,100,000	1,100,000
Employee Severance [Member]
Restructuring Charges, Total		600,000
Equipment Related, Freight and Other Costs [Member]
Restructuring Charges, Total		1,000,000
Restructuring and Related Cost, Expected Cost Remaining	2,400,000	2,400,000
Restructuring Reserve, Ending Balance	$ 1,100,000	$ 1,100,000