Note 2 - Summary of Significant Accounting Policies - Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
At January 1, 2022	$ 110	$ 223
Provision charged to expense	0	(19)
(Write-offs) / Recoveries	0	(94)
At December 31, 2022	$ 110	$ 110