Note 4 - Segment Reporting Information - Intersegment Revenues (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Revenue from Contract with Customer, Including Assessed Tax	$ 111,143	$ 76,387	$ 217,540	$ 146,393
Lighting Segment [Member]
Revenue from Contract with Customer, Including Assessed Tax	57,276	45,126	108,536	90,531
Display Solutions Segment [Member]
Revenue from Contract with Customer, Including Assessed Tax	53,867	31,261	109,004	55,862
Intersegment Eliminations [Member] | Lighting Segment [Member]
Revenue from Contract with Customer, Including Assessed Tax	11,266	5,038	21,723	9,118
Intersegment Eliminations [Member] | Display Solutions Segment [Member]
Revenue from Contract with Customer, Including Assessed Tax	$ 72	$ 75	$ 235	$ 113