Note I - Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2022

Notes Tables

Schedule of Finite-Lived Intangible Assets [Table Text Block]

	December 31, 2022
	Gross		Accumulated			Intangible
	Amount		amortization			assets, net
Patents	$	8,994	$	(5,330	)	$	3,664
Trademarks		56		(21	)	$	35
Total intangible assets	$	9,050	$	(5,351	)	$	3,699

	December 31, 2021
	Gross		Accumulated			Intangible
	Amount		amortization			assets, net
Patents	$	8,597	$	(4,779	)	$	3,818
Trademarks		35		(17	)		18
Total intangible assets	$	8,632	$	(4,796	)	$	3,836

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]

	December 31, 2022
2023	$	627
2024		627
2025		627
2026		627
2027		627
2028		564
thereafter		-
Total	$	3,699