Note N - Restructuring Activities - Changes in Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Beginning Balance:	$ 958	$ 1,472	$ 553	$ 1,921
Additions	97	1,187	1,528	5,167
Payments and adjustments	(421)	(1,873)	(1,447)	(6,302)
Ending Balance:	634	786	634	786
Contract Termination [Member]
Beginning Balance:	0	695	0	1,491
Additions	0	0	0	0
Payments and adjustments	0	(695)	0	(1,491)
Ending Balance:	0	0	0	0
Employee Severance [Member]
Beginning Balance:	937	775	549	360
Additions	113	611	1,527	2,022
Payments and adjustments	(421)	(608)	(1,447)	(1,604)
Ending Balance:	629	778	629	778
Facility, Asset Impairment and Other Expense [Member]
Beginning Balance:	21	2	4	70
Additions	(16)	576	1	3,145
Payments and adjustments	0	(570)	0	(3,207)
Ending Balance:	$ 5	$ 8	$ 5	$ 8