Note 8 - Capital Shares - Option Activity (Details) - $ / shares	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023
Balance, number of options (in shares)	420,615	314,853
Balance, options, weighted average exercise price (in dollars per share)	$ 25.6	$ 32.62
Balance, options, weighted average grant date fair value (in dollars per share)	$ 18.84	$ 23.94
Granted, number of options (in shares)	500	118,579
Granted, options, weighted average exercise price (in dollars per share)	$ 4.1	$ 7.47
Granted, options, weighted average grant date fair value (in dollars per share)	$ 3.1	$ 5.23
Forfeited, number of options (in shares)	(2,401)	(12,779)
Forfeited, options, weighted average exercise price (in dollars per share)	$ 15	$ 22.76
Forfeited, options, weighted average grant date fair value (in dollars per share)	$ 10.7	$ 16.23
Expired, number of options (in shares)	(35,674)	(38)
Expired, options, weighted average exercise price (in dollars per share)	$ 33.18	$ 1,973.2
Expired, options, weighted average grant date fair value (in dollars per share)	$ 25	$ 1,973.2
Balance, number of options (in shares)	383,040	420,615
Balance, options, weighted average exercise price (in dollars per share)	$ 24.93	$ 25.6
Balance, options, weighted average grant date fair value (in dollars per share)	$ 18.33	$ 18.84

Weighted average grant-date fair value of options outstanding.

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- Definition

Weighted average grant-date fair value of options expired.

+ References

No definition available.

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- Definition

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

+ References

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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- Definition

Weighted average grant-date fair value of non-vested options forfeited.

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No definition available.

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