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Note 13 - Subsequent Events (Details Textual) - USD ($) |  |  |  |  |  |  | 6 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Aug. 06, 2025 | Jul. 30, 2025 | Jul. 29, 2025 | Jul. 18, 2025 | Jul. 10, 2025 | Jul. 01, 2025 | Jun. 30, 2025 | Jun. 30, 2024 | Aug. 05, 2025 | Apr. 25, 2025
Debt Conversion, Original Debt, Amount |  |  |  |  |  |  | $ 12,500,000 | $ 0 |  |
Share Repurchase Program, Authorized, Amount |  |  |  |  |  |  |  |  |  | $ 5,000,000
Conversion of 2031 Notes Into Common Stock [Member] |  |  |  |  |  |  |  |  |  |
Debt Conversion, Original Debt, Amount |  |  |  |  |  |  | $ 12,500,000 |  |  |
Debt Conversion, Converted Instrument, Shares Issued (in shares) |  |  |  |  |  |  | 1,621,503 |  |  |
Debt Instrument, Convertible, Conversion Price (in dollars per share) |  |  |  |  |  |  | $ 7.79 |  |  |
Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |
Proceeds from Warrant Exercises |  |  |  |  |  | $ 2,700,000 |  |  |  |
Share Repurchase Program, Authorized, Amount |  |  |  |  |  |  |  |  | $ 10,000,000 |
Stock Repurchase Program, Percentage of Outstanding Stock Maximum |  |  |  |  |  |  |  |  | 2.00% |
Stock Repurchase Program, Maximum Percentage of Net Asset Value |  |  |  |  |  |  |  |  | 90.00% |
Subsequent Event [Member] | Assets of Powerscourt Investments XXV, LP [Member] |  |  |  |  |  |  |  |  |  |
Asset Acquisition, Consideration Transferred | $ 22,500,000 |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | Noodle Partners, Inc. [Member] | Debt Securities [Member] |  |  |  |  |  |  |  |  |  |
Proceeds from Sale, Maturity and Collection of Investments |  |  |  | $ 16,700,000 |  |  |  |  |  |
Subsequent Event [Member] | Tallac Therapeutics, Inc [Member] | Debt Securities [Member] |  |  |  |  |  |  |  |  |  |
Proceeds from Sale, Maturity and Collection of Investments |  |  |  | $ 2,000,000 |  |  |  |  |  |
Subsequent Event [Member] | Pivot Bio, Inc. [Member] | Debt Securities [Member] |  |  |  |  |  |  |  |  |  |
Proceeds from Sale, Maturity and Collection of Investments |  |  | $ 10,000,000 |  |  |  |  |  |  |
Subsequent Event [Member] | Native Microbials, Inc. [Member] | Debt Securities [Member] |  |  |  |  |  |  |  |  |  |
Proceeds from Sale, Maturity and Collection of Investments |  | $ 3,500,000 |  |  |  |  |  |  |  |
Subsequent Event [Member] | Conversion of 2031 Notes Into Common Stock [Member] |  |  |  |  |  |  |  |  |  |
Debt Conversion, Original Debt, Amount |  |  |  |  | $ 3,750,000 |  |  |  |  |
Debt Conversion, Converted Instrument, Shares Issued (in shares) |  |  |  |  | 496,256 |  |  |  |  |
Debt Instrument, Convertible, Conversion Price (in dollars per share) |  |  |  |  | $ 7.57 |  |  |  |  |

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- Definition Amount authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 505 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481520/505-30-50-4 + Details
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