Note N - Restructuring Activities (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Restructuring Charges, Total	$ 937	$ 1,419	$ 4,880	$ 8,005
Restructuring and Related Cost, Expected Cost, Total	27,100		27,100
Restructuring and Related Cost, Cost Incurred to Date	26,100		26,100
Restructuring and Related Cost, Expected Cost Remaining	1,000		1,000
Employee Severance [Member]
Restructuring Charges, Total	116	641	1,530	2,053
Lease Impairment and Termination Charges [Member]
Restructuring Charges, Total	425	0	718	2,974
Facility Closing [Member]
Restructuring Charges, Total	404	624	2,634	1,990
Capital Losses from Asset Disposal [Member]
Restructuring Charges, Total	$ (8)	$ 154	$ (2)	$ 1,294