Note D - Leases (Details Textual) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Lessee, Lease, Termination Period (Year)	1 year
Finance Lease, Right-of-Use Asset, after Accumulated Amortization, Total	$ 810	$ 957
Operating Lease, Right-of-Use Asset	19,569	23,793
Finance Lease, Right-of-Use Asset, Accumulated Depreciation	700	$ 500
Lessor, Operating Lease, Payment to be Received, Remainder of Fiscal Year	200
Lessor, Operating Lease, Payment to be Received, Year One	600
Lessor, Operating Lease, Payment to be Received, Year Two	$ 200
Minimum [Member]
Lessee, Lease Remaining Lease Term (Year)	1 year
Maximum [Member]
Lessee, Lease Remaining Lease Term (Year)	6 years
Lessee, Lease, Renewal Term (Year)	5 years