Note 8 - Property, Plant and Equipment - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jun. 30, 2018
Cost	$ 163,368	$ 163,323
Accumulated Depreciation	(126,689)	(126,809)
Property, Plant and Equipment, Net, Ending Balance	36,679	36,514
Land [Member]
Cost	1,210	1,210
Accumulated Depreciation
Property, Plant and Equipment, Net, Ending Balance	1,210	1,210
Building and Building Improvements [Member]
Cost	44,772	44,540
Accumulated Depreciation	(30,427)	(29,774)
Property, Plant and Equipment, Net, Ending Balance	14,345	14,766
Machinery and Equipment [Member]
Cost	117,386	117,573
Accumulated Depreciation	(96,262)	(97,035)
Property, Plant and Equipment, Net, Ending Balance	$ 21,124	$ 20,538

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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