Note J - Severance Expense (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Payment Arrangement, Expense	$ 385	$ 1,057	$ 2,034	$ 3,664
Severance Expense [Member]
Share-based Payment Arrangement, Expense			420
Employee Severance [Member] | Accounts Payable and Accrued Liabilities [Member]
Accrued Severance Expense	100	0	100	0
Employee Severance [Member] | Severance Expense [Member]
Severance Charges	$ 0	$ 0	400	$ 0
Share-based Payment Arrangement, Expense			$ 400