Note 14 - Restructuring Costs (Details Textual) - USD ($)	3 Months Ended	9 Months Ended
	Mar. 31, 2017	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Restructuring and Related Cost, Expected Cost	$ 424,000	$ 424,000
Inventory Write-down		981,000	$ 1,351,000
Gain (Loss) on Disposition of Property Plant Equipment		1,361,000
Restructuring Charges		1,386,000
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		32,000
Closure of Kansas City Facility [Member]
Restructuring and Related Cost, Expected Cost				$ 944,000
Inventory Write-down		432,000
Gain (Loss) on Disposition of Property Plant Equipment	$ 1,361,000
Closure of Kansas City Facility [Member] | Machinery and Equipment at the Kansas City and Beaverton Facilities [Member]
Impairment of Long-Lived Assets Held-for-use		354,000
Consolidation of Beaverton, Oregon Facility into Other LSI Facilities [Member]
Restructuring Charges		363,000
Consolidation of Woonsocket, Rhode Island Manufacturing Operation into Its North Canton, Ohio Operation [Member]
Restructuring and Related Cost, Expected Cost				$ 464,000
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		$ 354,000