Note 1 - Significant Accounting Policies and Related Matters - Allowance for Doubtful Accounts and Sales Returns (Details) - Allowance for Doubtful Accounts and Sales Returns [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Balance	$ 679	$ 623	$ 522
Additions (recoveries) charged to income	637	263	293
Deductions from reserves	481	207	192
Balance	$ 835	$ 679	$ 623