Note L - Convertible Senior Notes - Schedule of Interest Expense (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Amortization of debt issuance costs	$ 865	$ 900	$ 892
The 5% Convertible Senior Notes Due 2024 [Member]
Contractual interest expense	4,025	4,025
Amortization of debt issuance costs	826	831
Total interest cost	$ 4,851	$ 4,856
Effective interest rate	5.10%	5.10%

Amount of the cost of borrowed funds accounted for as interest expense for debt.

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