Note 4 - Segment Reporting Information - Summarized Financial Information by Operating Segments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021
Net Sales	$ 110,111	$ 72,204	$ 327,651	$ 218,597
Operating income (loss)	5,161	2,096	14,027	6,984
Capital expenditures	531	637	1,276	1,517
Depreciation and amortization	2,531	1,920	7,632	5,943
Corporate and Eliminations [Member]
Operating income (loss)	(4,354)	(2,931)	(12,036)	(8,731)
Capital expenditures	74	15	(8)	184
Depreciation and amortization	60	76	203	208
Lighting Segment [Member]
Net Sales	57,126	45,740	165,662	136,271
Lighting Segment [Member] | Operating Segments [Member]
Operating income (loss)	4,959	3,797	13,921	9,519
Capital expenditures	272	605	624	1,249
Depreciation and amortization	1,450	1,566	4,361	4,795
Display Solutions Segment [Member]
Net Sales	52,985	26,464	161,989	82,326
Display Solutions Segment [Member] | Operating Segments [Member]
Operating income (loss)	4,556	1,230	12,142	6,196
Capital expenditures	185	17	660	84
Depreciation and amortization	$ 1,021	$ 278	$ 3,068	$ 940