Note D - Leases - Maturities of Finance and Operating Lease Liabilities (Details) - USD ($) $ in Thousands		Dec. 31, 2020		Dec. 31, 2019
2021, operating leases	[1]	$ 7,274
2021, finance leases		252
2022, operating leases	[1]	5,870
2022, finance leases		209
2023, operating leases	[1]	4,616
2023, finance leases		166
2024, operating leases	[1]	3,314
2024, finance leases		48
2025, operating leases	[1]	1,574
2025, finance leases		6
2026, operating leases	[1]	7,505
2026, finance leases
Total future minimum lease payments, operating leases	[1]	30,153
Total future minimum lease payments, finance leases		681
Less: Imputed interest, operating leases	[1]	2,825
Less: Imputed interest, finance leases		51
Total lease liabilities, finance leases		630
Short-term Lease Liabilities and Long-term Lease Liabilities [Member]
Total lease liabilities, operating leases		27,328	[1]	$ 19,740
Total lease liabilities, finance leases		$ 630		$ 954

[1] Non-cancelable sublease proceeds for the fiscal year ending December 31, 2021, 2022, and 2023 of $647k, $540k, and $154k,respectively, are not included in the table above.