Note 3 - Segment Reporting Information - Intersegment Revenues (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Inter-segment Revenues	$ 76,387	$ 82,377	$ 146,393	$ 171,078
Lighting Segment [Member]
Inter-segment Revenues	45,126	53,436	90,531	116,627
Graphics Segment [Member]
Inter-segment Revenues	31,261	28,941	55,862	54,451
Intersegment Eliminations [Member] | Lighting Segment [Member]
Inter-segment Revenues	5,038	860	9,118	1,671
Intersegment Eliminations [Member] | Graphics Segment [Member]
Inter-segment Revenues	$ 75	$ 74	$ 113	$ 98