Note D - Leases - Components of Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Operating lease cost	$ 1,853	$ 1,951	$ 5,885	$ 6,435
Amortization of right-of-use assets	49	59	147	191
Interest on lease liabilities	6	10	21	37
Total Finance lease cost	55	69	168	228
Variable lease cost	577	604	2,131	2,246
Sublease income	(117)	(228)	(475)	(228)
Total lease cost, net	$ 2,368	$ 2,396	7,709	8,681
Operating cash flows from operating leases			11,179	14,535
Operating cash flows from finance leases			19	32
Financing cash flows from finance leases			$ 169	$ 357
Weighted Average Remaining Lease term, Operating leases (Year)	5 years 9 months 18 days	3 years	5 years 9 months 18 days	3 years
Weighted Average Remaining Lease term, Finance leases (Year)	2 years 3 months 18 days	3 years 2 months 12 days	2 years 3 months 18 days	3 years 2 months 12 days
Weighted Average Discount Rate, Operating leases	3.50%	4.67%	3.50%	4.67%
Weighted Average Discount Rate, Finance leases	5.36%	5.28%	5.36%	5.28%