Note 14 - Restructuring Costs (Details Textual) - USD ($)	3 Months Ended	6 Months Ended
	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Restructuring and Related Cost, Expected Cost		$ 1,562,000
Inventory Write-down		758,000	$ 699,000
Restructuring Charges		1,000,000
Impairment of Long-Lived Assets Held-for-use		354,000
Machinery and Equipment at the Kansas City and Beaverton Facilities [Member] | Lighting Segment [Member]
Impairment of Long-Lived Assets Held-for-use		322,000
Machinery and Equipment at the Kansas City and Beaverton Facilities [Member] | Technology Segment [Member]
Impairment of Long-Lived Assets Held-for-use		31,000
Closure of Kansas City Facility [Member]
Restructuring and Related Cost, Expected Cost		900,000
Inventory Write-down	$ 400,000
Consolidation of Beaverton, Oregon Facility into Other LSI Facilities [Member]
Restructuring Charges		362,000
Consolidation of Woonsocket, Rhode Island Manufacturing Operation into Its North Canton, Ohio Operation [Member]
Restructuring and Related Cost, Expected Cost		300,000
Closure of Kansas City Facility and Consolidation of Beaverton, Oregon Facility Into Other LSI Facilities [Member] | Machinery and Equipment at the Kansas City and Beaverton Facilities [Member]
Impairment of Long-Lived Assets Held-for-use		$ 353,000