Note 3 - Segment Reporting Information - Summarized Financial Information by Reportable Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Net sales	$ 88,701	$ 84,957
Operating income (loss)	6,839	2,934
Capital expenditures	355	648
Depreciation and Amortization:
Depreciation and amortization	2,399	2,643
Corporate and Eliminations [Member]
Operating income (loss)	(3,337)	(3,303)
Capital expenditures	25	106
Depreciation and Amortization:
Depreciation and amortization	235	258
Lighting Segment [Member]
Net sales	63,191	61,432
Lighting Segment [Member] \| Operating Segments [Member]
Operating income (loss)	9,159	3,850
Capital expenditures	330	276
Depreciation and Amortization:
Depreciation and amortization	1,778	1,990
Graphics Segment [Member]
Net sales	25,510	23,525
Graphics Segment [Member] \| Operating Segments [Member]
Operating income (loss)	1,017	2,387
Capital expenditures		266
Depreciation and Amortization:
Depreciation and amortization	$ 386	$ 395

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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