Note 7 - Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Federal tax benefit at statutory rate	$ 6,251	$ 6,096
Federal tax benefit at statutory rate, percentage	21.00%	21.00%
State tax benefit net of federal	$ 118	$ 347
State tax benefit net of federal, percentage	0.40%	1.20%
Foreign rate differential	$ 59	$ 10
Foreign rate differential, percentage	0.20%	0.00%
Stock warrant costs	$ (219)	$ 280
Stock warrant costs, percentage	(0.80%)	1.00%
Other permanent differences	$ (73)	$ (145)
Other permanent differences, percentage	(0.20%)	(0.50%)
Permanent provision to return items	$ 662	$ 395
Permanent provision to return items, percentage	2.30%	1.40%
Stock compensation change	$ (82)	$ (49)
Stock compensation change, percentage	(0.30%)	(0.20%)
Uncertain tax provision	$ (103)	$ (61)
Uncertain tax provision, percentage	(0.40%)	(0.20%)
Increase in valuation allowance	$ (6,613)	$ (6,873)
Increase in valuation allowance, percentage	(22.20%)	(23.70%)
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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Represents permanent PRT items for effective income tax rate reconciliation.

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Represents stock warrant costs for effective income tax 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 attributable to changes in the valuation allowance for deferred tax assets.

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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 attributable to income tax contingencies. Includes, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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