Note 14 - Restructuring Costs (Details Textual) - USD ($)	3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017	Dec. 31, 2016
Inventory Write-down		$ 143,000	$ 573,000
Restructuring Charges
Closure of Kansas City Facility [Member]
Restructuring and Related Cost, Expected Cost	0	0			$ 944,000
Inventory Write-down				$ 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	$ 0	$ 0			$ 452,000