| Note 6 - Related Party Transactions (Details Textual) $ in Thousands | 12 Months Ended | 
|---|---|
| Dec. 31, 2023  USD ($) | |
| Tactic Pharma, LLC [Member] | |
| Related Party Transaction, Amounts of Transaction | $ 0 | 
| Tactic Pharma, LLC [Member] | Monopar Therapeutics [Member] | |
| Equity Method Investment, Ownership Percentage | 29.00% | 
| X | ||||||||||
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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| X | ||||||||||
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- Definition Amount of transactions with related party during the financial reporting period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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| X | ||||||||||
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- Details 
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| X | ||||||||||
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- Details 
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| X | ||||||||||
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- Details 
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