Note O - Income Taxes - Net Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
NOL carryforward	$ 49,469	$ 47,901
Inventory reserves	3,195	2,892
Unrealized gains and losses	355	363
Share-based compensation	1,013	914
Foreign tax credit	4,599	4,599
Research and development credits	10,998	10,505
Capitalized research and development	8,717
Interest	5,659	3,966
ASC 842 Assets	1,561	1,602
Other	941	776
Deferred tax assets	86,507	73,518
Less valuation allowance	(78,124)	(69,680)	$ (69,680)	$ (57,721)	$ (43,462)
Deferred tax assets, net	8,383	3,838
Depreciation and amortization	(6,992)	(2,441)
ASC 842 Liabilities	(1,391)	(1,397)
Deferred tax liabilities	(8,383)	(3,838)
Deferred tax assets (liabilities), net	$ 0	$ 0