Note 7 - Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Federal tax benefit at statutory rate	$ 6,096	$ 3,338
Federal tax benefit at statutory rate, percentage	21.00%	21.00%
State tax benefit net of federal	$ 347	$ 25
State tax benefit net of federal, percentage	1.20%	0.20%
Foreign rate differential	$ 10	$ 7
Foreign rate differential, percentage	0.00%	0.00%
Stock warrant costs	$ 280	$ 1,413
Stock warrant costs, percentage	1.00%	8.90%
Other permanent differences	$ (145)	$ (77)
Other permanent differences, percentage	(0.50%)	(0.50%)
Permanent provision to return items	$ 395	$ 344
Permanent provision to return items, percentage	1.40%	2.20%
Stock compensation change	$ (49)	$ (37)
Stock compensation change, percentage	(0.20%)	(0.20%)
Uncertain tax provision	$ (61)	$ (57)
Uncertain tax provision, percentage	(0.20%)	(0.40%)
Increase in valuation allowance	$ (6,873)	$ (4,956)
Increase in valuation allowance, percentage	(23.70%)	(31.20%)
Total tax (expense) benefit	$ 0	$ 0
Total tax (expense) benefit, percentage	0.00%	0.00%

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Percentage of other permanent difference for effective income tax rate reconciliation.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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