Note 4 - Fair Value Measurement and Fair Value of Financial Instruments (Details Textual) $ in Thousands	3 Months Ended
Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Sep. 30, 2025 USD ($)
Long-Term Debt, Fair Value	$ 200		$ 300
Long-Term Debt	236		$ 326
Fair Value Adjustment of Warrants	$ (90)	$ 114
Measurement Input, Price Volatility [Member] \| Valuation, Market Approach [Member]
Warrants and Rights Outstanding, Measurement Input			0.40
Measurement Input, Price Volatility [Member] \| Valuation, Market Approach [Member] \| Minimum [Member]
Warrants and Rights Outstanding, Measurement Input	0.244		0.251
Measurement Input, Price Volatility [Member] \| Valuation, Market Approach [Member] \| Maximum [Member]
Warrants and Rights Outstanding, Measurement Input	0.913		0.784
Measurement Input, Price Volatility [Member] \| Valuation, Market Approach [Member] \| Weighted Average [Member]
Warrants and Rights Outstanding, Measurement Input	0.491		0.479
Measurement Input, Price Volatility [Member] \| Valuation Technique, Company Specific Volatility [Member]
Warrants and Rights Outstanding, Measurement Input			0.60

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.

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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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