Note 10 - Stock Options and Stock Purchase Warrants - Summary of Option Activity (Details) - $ / shares	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Outstanding (in shares)	180,000	60,000
Outstanding (in dollars per share)	$ 5.93	$ 6.93
Granted (in shares)	0	120,000
Granted (in dollars per share)	$ 0	$ 5.43
Exercised (in shares)	0	0
Exercised (in dollars per share)	$ 0	$ 0
Forfeited or expired (in shares)	0	0
Forfeited or expired (in dollars per share)	$ 0	$ 0
Outstanding (in shares)	180,000	180,000
Outstanding (in dollars per share)	$ 5.93	$ 5.93

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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Weighted average price of options that were either forfeited or expired.

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

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