Note J - Fair Value of Financial Instruments - Financial Instruments Measured at Fair Value on a Recurring Basis (Details) - Fair Value, Recurring [Member] - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Cash and cash equivalents	$ 24,685	$ 34,656
Restricted cash	10,902	6,480
Note receivable	339	8,148
Total assets	35,926	49,284
Bank acceptance payable	12,337	8,198
Convertible senior notes	58,314	67,588
Total liabilities	70,651	75,786
Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	24,685	34,656
Restricted cash	10,902	6,480
Note receivable	0	0
Total assets	35,587	41,136
Bank acceptance payable	0	0
Convertible senior notes	0	0
Total liabilities	0	0
Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0	0
Restricted cash	0	0
Note receivable	339	8,148
Total assets	339	8,148
Bank acceptance payable	12,337	8,198
Convertible senior notes	58,314	67,588
Total liabilities	70,651	75,786
Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents	0	0
Restricted cash	0	0
Note receivable	0	0
Total assets	0	0
Bank acceptance payable	0	0
Convertible senior notes	0	0
Total liabilities	$ 0	$ 0