Note D - Leases (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Operating Lease, Right-of-Use Asset	$ 19,179	$ 17,679
Operating Lease, Liability, Total	$ 21,572	21,730
Lessee, Lease, Termination Period (Year)	1 year
Finance Lease, Right-of-Use Asset, after Accumulated Amortization, Total	$ 1,071	$ 1,138
Finance Lease, Right-of-Use Asset, Accumulated Depreciation	400
Lessee, Operating Lease, Lease Not Yet Commenced, Liability	$ 0
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
Accounting Standards Update 2016-02 [Member]
Operating Lease, Right-of-Use Asset			$ 22,800
Operating Lease, Liability, Total			$ 23,900