Note 4 - Fair Value Measurement and Fair Value of Financial Instruments (Details Textual) $ in Thousands	3 Months Ended
Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Sep. 30, 2023 USD ($)
Long-Term Debt, Fair Value	$ 600		$ 600
Long-Term Debt	646		$ 700
Fair Value Adjustment of Warrants	$ (18)	$ (297)
Measurement Input, Price Volatility [Member] \| Valuation, Market Approach [Member]
Warrants and Rights Outstanding, Measurement Input	0.40
Measurement Input, Price Volatility [Member] \| Valuation Technique, Company Specific Volatility [Member]
Warrants and Rights Outstanding, Measurement Input	0.60
Minimum [Member] \| Measurement Input, Price Volatility [Member] \| Valuation, Market Approach [Member]
Warrants and Rights Outstanding, Measurement Input	0.223		0.277
Maximum [Member] \| Measurement Input, Price Volatility [Member] \| Valuation, Market Approach [Member]
Warrants and Rights Outstanding, Measurement Input	0.819		0.845
Weighted Average [Member] \| Measurement Input, Price Volatility [Member] \| Valuation, Market Approach [Member]
Warrants and Rights Outstanding, Measurement Input	0.419		0.455

Amount of expense (income) related to adjustment to fair value of warrant liability.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Value of input used to measure outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur.

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