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Note 12 - Subsequent Events (Details Textual) - USD ($) $ in Thousands				1 Months Ended	3 Months Ended
	Apr. 22, 2024	Apr. 11, 2024	Apr. 01, 2024	Apr. 30, 2024	Mar. 31, 2024	Mar. 31, 2023
Proceeds from Issuance of Common Stock					$ 11,972	$ 7,174
Subsequent Event [Member] | Provivi, Inc. [Member] | Debt Securities [Member]
Proceeds from Sale, Maturity and Collection of Investments			$ 4,700
Proceeds from Debt Securities, End-of-term, Amount			$ 300
Subsequent Event [Member] | Better Place Forests Co. [Member]
Payments to Acquire Investments		$ 500
Subsequent Event [Member] | CAMP NYC, Inc [Member] | Debt Securities [Member]
Proceeds from Sale, Maturity and Collection of Investments	$ 1,000
The 2023 Equity Distribution Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares)					1,053,796
Proceeds from Issuance of Common Stock					$ 12,000
Payments of Stock Issuance Costs					$ 300
The 2023 Equity Distribution Agreement [Member] | Subsequent Event [Member]
Stock Issued During Period, Shares, New Issues (in shares)				526,581
Proceeds from Issuance of Common Stock				$ 5,800
Payments of Stock Issuance Costs				$ 100

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The cash outflow for cost incurred directly with the issuance of an equity security.

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