Note 2 - Summarized Financial Information by Reportable Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2016		Jun. 30, 2015		Jun. 30, 2014		Jun. 30, 2013	Jun. 30, 2012
Lighting Segment [Member]
Net Sales:
Net Sales													$ 226,889		$ 219,920		$ 222,604
Operating Income (Loss):
Operating Income (Loss)													15,785		14,775		10,524
Capital Expenditures:
Capital Expenditures													4,255		1,905		3,294
Depreciation and Amortization:
Depreciation and Amortization													2,930		2,965		2,779
Graphics Segment [Member]
Net Sales:
Net Sales													77,039		64,895		50,970
Operating Income (Loss):
Operating Income (Loss)													5,429		1,156		(2,086)
Capital Expenditures:
Capital Expenditures													3,605		1,100		461
Depreciation and Amortization:
Depreciation and Amortization													1,015		979		950
Technology Segment [Member]
Net Sales:
Net Sales													18,268		23,001		24,515
Operating Income (Loss):
Operating Income (Loss)													3,845		2,949		1,633
Capital Expenditures:
Capital Expenditures													1,935		1,146		726
Depreciation and Amortization:
Depreciation and Amortization													1,518		1,341		1,563
All Other Category [Member]
Net Sales:
Net Sales															41		1,374
Operating Income (Loss):
Operating Income (Loss)															(183)		(854)
Capital Expenditures:
Capital Expenditures															4		20
Depreciation and Amortization:
Depreciation and Amortization															31		161
Corporate and Eliminations [Member]
Operating Income (Loss):
Operating Income (Loss)													(11,103)		(11,164)		(6,899)
Capital Expenditures:
Capital Expenditures													416		599		744
Depreciation and Amortization:
Depreciation and Amortization													1,214		1,015		773
Net Sales	$ 80,844	$ 70,740	$ 84,687	$ 85,925	$ 76,073	$ 68,603	$ 84,715	$ 78,466	$ 73,858	$ 68,996	$ 76,123	$ 80,486	322,196	[1]	307,857	[1]	299,463	[1]	$ 280,790	$ 268,402
Operating Income (Loss)													13,956		7,533		2,318		$ 630	$ 6,331
Capital Expenditures													10,211		4,754		5,245
Depreciation and Amortization													$ 6,677		$ 6,331		$ 6,226

[1] Net sales are attributed to geographic areas based upon the location of the operation making the sale.