Note 8 - Income Taxes - Schedule of Income Tax Net of Refunds (Details) - USD ($)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Total cash paid for income taxes (net of refunds)	$ 1,037,209	$ 1,123,024
Internal Revenue Service (IRS) [Member]
Income Tax Paid, Federal	0	0
Minnesota Department of Revenue [Member]
Income Tax Paid, State and Local	1,037,209	845,000
Iowa Department of Revenue [Member]
Income Tax Paid, State and Local	$ 0	$ 278,024

Amount, after income tax refund received, of cash paid to federal (national) tax jurisdiction for tax on income.

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Amount, after income tax refund received, of cash paid to state and local tax jurisdictions for tax on income.

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Amount, after refund, of cash paid to foreign, federal, state, and local jurisdictions as income tax.

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-Topic 230
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