Note 4 - Segment Reporting Information - Summarized Financial Information by Operating Segments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Net Sales	$ 111,143	$ 76,387	$ 217,540	$ 146,393
Operating income (loss)	4,422	2,686	8,866	4,888
Capital expenditures	448	475	745	880
Depreciation and amortization	2,538	1,990	5,101	4,023
Corporate and Eliminations [Member]
Operating income (loss)	(4,038)	(2,591)	(7,682)	(5,800)
Capital expenditures	22	160	(82)	169
Depreciation and amortization	72	76	143	132
Lighting Segment [Member]
Net Sales	57,276	45,126	108,536	90,531
Lighting Segment [Member] | Operating Segments [Member]
Operating income (loss)	4,623	2,134	8,962	5,722
Capital expenditures	172	275	352	644
Depreciation and amortization	1,450	1,610	2,911	3,229
Display Solutions Segment [Member]
Net Sales	53,867	31,261	109,004	55,862
Display Solutions Segment [Member] | Operating Segments [Member]
Operating income (loss)	3,837	3,143	7,586	4,966
Capital expenditures	254	40	475	67
Depreciation and amortization	$ 1,016	$ 304	$ 2,047	$ 662