Note 14 - Restructuring Costs (Details Textual) - USD ($)	3 Months Ended	6 Months Ended		12 Months Ended
	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2017
Inventory Write-down		$ 1,033,000	$ 758,000
Restructuring Charges
Closure of Kansas City Facility [Member]
Restructuring and Related Cost, Expected Cost		0		$ 944,000
Inventory Write-down	$ 400,000			485,000
Gain (Loss) on Disposition of Property Plant Equipment				1,361,000
Consolidation of Beaverton, Oregon Facility into Other LSI Facilities [Member]
Restructuring Charges		0		377,000
Consolidation of Woonsocket, Rhode Island Manufacturing Operation into Its North Canton, Ohio Operation [Member]
Restructuring and Related Cost, Expected Cost				$ 452,000
Restructuring Charges		$ 0