Note D - Leases - Maturities of Finance and Operating Lease Liabilities (Details) - USD ($) $ in Thousands		Sep. 30, 2021		Dec. 31, 2020
Remainder of 2021, operating leases	[1]	$ 1,997
Remainder of 2021, finance leases		63
2022, operating leases	[1]	6,698
2022, finance leases		209
2023, operating leases	[1]	4,765
2023, finance leases		166
2024, operating leases	[1]	3,327
2024, finance leases		48
2025, operating leases	[1]	1,581
2025, finance leases		6
2026, operating leases	[1]	7,505
2026, finance leases		0
Total future minimum lease payments, operating leases	[1]	25,873
Total future minimum lease payments, finance leases		492
Less: Imputed interest, operating leases	[1]	2,174
Less: Imputed interest, finance leases		30
Total lease liabilities, finance leases		462
Short-term Lease Liabilities and Long-term Lease Liabilities [Member]
Total lease liabilities, operating leases		23,699	[1]	$ 27,328
Total lease liabilities, finance leases		$ 462		$ 630

[1] Non-cancelable sublease proceeds for the remainder of the fiscal year ending December 31, 2021 and the fiscal years ending December 31, 2022 and 2023 of $0.2 million, $0.6 million, and $0.2 million, respectively, are not included in the table above.