Note 3 - Property and Equipment, Net - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Jun. 30, 2021
Property and equipment, gross	$ 9,145	$ 9,036
Less: Accumulated depreciation and amortization	(7,347)	(7,294)
Total	1,798	1,742
Land and Building [Member]
Property and equipment, gross	1,250	1,250
Leasehold Improvements [Member]
Property and equipment, gross	1,371	1,364
Machinery and Equipment [Member]
Property and equipment, gross	6,518	6,416
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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