Note 7 - Stock-based Compensation (Details Textual) - USD ($)	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Number of Shares (in shares)	912,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value (in dollars per share)	$ 2,074,670	$ 176,900
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)		145,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period (in shares)	105,000	0
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 2,966,854
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Month)	11 months
Share-Based Payment Arrangement, Expense	$ 312,176	$ 27,711

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Gross number of share options (or share units) granted during the period.

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Number of options vested.

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No definition available.

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Weighted average grant-date fair value of options vested.

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Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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