Note 6 - Goodwill and Other Intangible Assets - Goodwill (Details) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Goodwill, net		$ 30,538,000	$ 58,538,000
Goodwill impairment		(28,000,000)	(479,000)
Lighting Segment [Member]
Goodwill		94,564,000	94,564,000
Accumulated impairment losses		(65,191,000)	(37,191,000)
Goodwill, net		29,373,000	57,373,000
Goodwill impairment	$ (28,000,000)	(28,000,000)
Graphics Segment [Member]
Goodwill		28,690,000	28,690,000
Accumulated impairment losses		(27,525,000)	(27,525,000)
Goodwill, net		1,165,000	1,165,000
Goodwill impairment
Technology Segment [Member]
Goodwill		123,254,000	123,254,000
Accumulated impairment losses		(92,716,000)	(64,716,000)
Goodwill, net		30,538,000	$ 58,538,000
Goodwill impairment		$ (28,000,000)