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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

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+ References

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- Definition

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+ References

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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
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+ References

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

+ References

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The amount of the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The price per share of the conversion feature embedded in the debt instrument.

+ References

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The cash inflow associated with the sale, maturity and collection of all investments such as debt, security and so forth during the period.

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