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Note 13 - Subsequent Events (Details Textual) - USD ($) $ in Thousands											1 Months Ended		12 Months Ended
	Mar. 04, 2025	Feb. 28, 2025	Feb. 27, 2025	Feb. 25, 2025	Jan. 31, 2025	Jan. 15, 2025	Jan. 10, 2025	Jan. 09, 2025	Jan. 07, 2025	Jan. 02, 2025	Feb. 25, 2025	Jan. 23, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Proceeds from Issuance of Common Stock													$ 66,353	$ 65,093	$ 84,603
The 2023 Equity Distribution Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares)													6,300,095
Proceeds from Issuance of Common Stock													$ 66,400
Payments of Stock Issuance Costs													$ 1,400
Subsequent Event [Member] | The 2023 Equity Distribution Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares)												404,305
Proceeds from Issuance of Common Stock												$ 3,700
Payments of Stock Issuance Costs												$ 100
Pivot Bio, Inc. [Member] | Debt Securities [Member] | Subsequent Event [Member]
Payments to Acquire Investments										$ 20,000
Proceeds from Sale, Maturity and Collection of Investments									$ 20,000
Hound Labs, Inc. [Member] | Debt Securities [Member] | Subsequent Event [Member]
Payments to Acquire Investments								$ 500
Investment Owned, Balance, Principal Amount								$ 2,900
HappyCo, Inc [Member] | Debt Securities [Member] | Subsequent Event [Member]
Payments to Acquire Investments							$ 6,000
Swift Health Systems Inc. [Member] | Equity Securities [Member] | Subsequent Event [Member]
Payments to Acquire Investments						$ 2,000
Britecore Holdings, Inc. [Member] | Debt Securities [Member] | Subsequent Event [Member]
Payments to Acquire Investments					$ 2,500
Better Place Forests Co. [Member] | Debt Securities [Member] | Subsequent Event [Member]
Payments to Acquire Investments											$ 400
Castle Creek Pharmaceuticals Holdings, Inc. [Member] | Debt Securities [Member] | Subsequent Event [Member]
Payments to Acquire Investments				$ 25,500
Proceeds from Sale, Maturity and Collection of Investments				$ 16,300
Long Grove Pharmaceutical, LLC [Member] | Debt Securities [Member] | Subsequent Event [Member]
Payments to Acquire Investments			$ 10,000
MML US, Inc [Member] | Debt Securities [Member] | Subsequent Event [Member]
Payments to Acquire Investments		$ 15,000
Candesant Biomedical, Inc. [Member] | Debt Securities [Member] | Forecast [Member]
Proceeds from Sale, Maturity and Collection of Investments	$ 10,000

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