Note 3 - Summary of Significant Accounting Policies - Basic and Diluted Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Net income	$ 1,964	$ 1,446	$ 2,120	$ 2,736
Weighted average common shares - basic (in shares)	4,446	4,556	4,464	4,555
Dilutive effect of outstanding warrants and stock options (in shares)	441	404	442	416
Weighted average common shares - diluted (in shares)	4,887	4,960	4,906	4,971
Basic (in dollars per share)	$ 0.44	$ 0.32	$ 0.47	$ 0.60
Diluted (in dollars per share)	$ 0.40	$ 0.29	$ 0.43	$ 0.55