Note 8 - Income Taxes - Summary of Income Tax Contingencies (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Balance	$ 96,000	$ 0
Increase related to prior year tax positions	0	36,000
Increase related to current year tax positions	159,000	60,000
Balance	$ 255,000	$ 96,000