Note 3 - Segment Reporting Information - Intersegment Revenues (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Inter-segment Revenues	$ 92,305	$ 85,658	$ 179,771	$ 169,817
Lighting Segment [Member]
Inter-segment Revenues	69,174	65,076	137,602	130,341
Graphics Segment [Member]
Inter-segment Revenues	23,131	20,582	42,169	39,476
Intersegment Eliminations [Member] | Lighting Segment [Member]
Inter-segment Revenues	992	700	1,707	1,453
Intersegment Eliminations [Member] | Graphics Segment [Member]
Inter-segment Revenues	$ 1,040	$ 680	$ 1,071	$ 812