Note 10 - Income Taxes - Unrecognized Tax Benefits Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Unrecognized tax benefits balance	$ 31	$ 31
Gross decrease in tax positions of prior years	0	0
Unrecognized tax benefits balance	$ 31	$ 31