Note 14 - Restructuring Costs (Details Textual) - USD ($)	3 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Closure of Kansas City Facility [Member]
Restructuring and Related Cost, Expected Cost	$ 1,000,000
Inventory Write-down	400,000
Restructuring, Estimated Annual Net Operating Profit Improvement and Costs Savings, Amount	1,400,000
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	273,000
Consolidation of Beaverton, Oregon Facility into Other LSI Facilities [Member]
Restructuring, Estimated Annual Net Operating Profit Improvement and Costs Savings, Amount	450,000
Restructuring Charges	365,000
Machinery and Equipment at the Kansas City and Beaverton Facilities [Member] | Lighting Segment [Member]
Impairment of Long-Lived Assets Held-for-use	242,000
Machinery and Equipment at the Kansas City and Beaverton Facilities [Member] | Technology Segment [Member]
Impairment of Long-Lived Assets Held-for-use	31,000
Restructuring and Related Cost, Expected Cost	1,342,000
Inventory Write-down	573,000	$ 367,000
Restructuring Charges	383,000
Impairment of Long-Lived Assets Held-for-use	$ 273,000