Note 7 - Capital Shares - Option Activity (Details) - $ / shares	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
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
Granted, number of options (in shares)		500
Granted, options, weighted average exercise price (in dollars per share)		$ 4.1
Granted, options, weighted average grant date fair value (in dollars per share)		$ 3.1
Forfeited, number of options (in shares)	(196)	(2,401)
Forfeited, options, weighted average exercise price (in dollars per share)	$ 4.1	$ 15
Forfeited, options, weighted average grant date fair value (in dollars per share)	$ 3.1	$ 10.7
Expired, number of options (in shares)	(4,805)	(35,674)
Expired, options, weighted average exercise price (in dollars per share)	$ 44.18	$ 33.18
Expired, options, weighted average grant date fair value (in dollars per share)	$ 37.95	$ 24.63
Balance, number of options (in shares)	378,039	383,040
Balance, options, weighted average exercise price (in dollars per share)	$ 24.7	$ 24.93
Balance, options, weighted average grant date fair value (in dollars per share)	$ 18.12	$ 18.33