Note 6 - Goodwill and Other Intangible Assets - Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2017	Jun. 30, 2016
Goodwill, net	$ 58,538	$ 10,508
Lighting Segment [Member]
Goodwill, net	48,165	135
Goodwill acquired	48,030
Goodwill	82,943	34,913
Accumulated impairment losses	(34,778)	(34,778)
Graphics Segment [Member]
Goodwill, net	1,165	1,165
Goodwill acquired
Goodwill	28,690	28,690
Accumulated impairment losses	(27,525)	(27,525)
Technology Segment [Member]
Goodwill, net	9,208	9,208
Goodwill acquired
Goodwill	11,621	11,621
Accumulated impairment losses	(2,413)	(2,413)
All Other Category [Member]
Goodwill, net	58,538	10,508
Goodwill acquired	48,030
Goodwill	123,254	75,224
Accumulated impairment losses	$ (64,716)	$ (64,716)

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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