Note C - Property and Equipment - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2020	Jun. 30, 2020
Property and equipment, gross	$ 63,430	$ 61,952
Less: accumulated depreciation and amortization	(41,391)	(40,429)
Property and equipment, net	22,039	21,523
Land [Member]
Property and equipment, gross	1,200	1,200
Building and Building Improvements [Member]
Property and equipment, gross	$ 3,743	3,743
Building and Building Improvements [Member] \| Minimum [Member]
Depreciable Life In Years (Year)	7 years
Building and Building Improvements [Member] \| Maximum [Member]
Depreciable Life In Years (Year)	39 years
Machinery and Equipment [Member]
Property and equipment, gross	$ 34,755	33,405
Machinery and Equipment [Member] \| Minimum [Member]
Depreciable Life In Years (Year)	3 years
Machinery and Equipment [Member] \| Maximum [Member]
Depreciable Life In Years (Year)	12 years
Office Equipment [Member]
Property and equipment, gross	$ 5,360	5,318
Office Equipment [Member] \| Minimum [Member]
Depreciable Life In Years (Year)	3 years
Office Equipment [Member] \| Maximum [Member]
Depreciable Life In Years (Year)	5 years
Vehicles [Member]
Property and equipment, gross	$ 255	255
Depreciable Life In Years (Year)	3 years
Leasehold Improvements [Member]
Property and equipment, gross	$ 18,117	$ 18,031
Leasehold Improvements [Member] \| Minimum [Member]
Depreciable Life In Years (Year)	1 year
Leasehold Improvements [Member] \| Maximum [Member]
Depreciable Life In Years (Year)	15 years

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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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