Note 4 - Property and Equipment, Net - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Jun. 30, 2019
Property and equipment, gross	$ 9,008	$ 8,818
Less: Accumulated depreciation and amortization	(7,312)	(7,040)
Total	1,696	1,778
Land and Building [Member]
Property and equipment, gross	1,250	1,250
Leasehold Improvements [Member]
Property and equipment, gross	1,287	1,282
Machinery and Equipment [Member]
Property and equipment, gross	6,465	6,280
Transportation Equipment [Member]
Property and equipment, gross	$ 6	$ 6

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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