The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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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.

+ References

+ Details

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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Note 5 - Capital Shares - Options Outstanding and Exercisable (Details) - $ / shares	9 Months Ended
	Jun. 30, 2026	Sep. 30, 2025	Jun. 30, 2025	Sep. 30, 2024
Options, number (in shares)	378,039	378,039	378,235	383,040
Options, exercisable (in shares)	378,039
Options, weighted average exercise price (in dollars per share)	$ 24.7	$ 24.7	$ 24.66	$ 24.93
Range One [Member]
Options, number (in shares)	37,719
Options, exercisable (in shares)	37,719
Options, weighted average exercise price (in dollars per share)	$ 15.12
Range Two [Member]
Options, number (in shares)	43,031
Options, exercisable (in shares)	43,031
Options, weighted average exercise price (in dollars per share)	$ 22.12
Range Three [Member]
Options, number (in shares)	51,006
Options, exercisable (in shares)	51,006
Share-Based Payment Arrangement, Option, Exercise Price Range, Lower Range Limit (in dollars per share)	$ 52.08
Share-Based Payment Arrangement, Option, Exercise Price Range, Upper Range Limit (in dollars per share)	$ 56.49
Range Four [Member]
Options, number (in shares)	79,651
Options, exercisable (in shares)	79,651
Share-Based Payment Arrangement, Option, Exercise Price Range, Lower Range Limit (in dollars per share)	$ 36.75
Share-Based Payment Arrangement, Option, Exercise Price Range, Upper Range Limit (in dollars per share)	$ 40.18
Range Five [Member]
Options, number (in shares)	56,865
Options, exercisable (in shares)	56,865
Options, weighted average exercise price (in dollars per share)	$ 25.97
Range Six [Member]
Options, number (in shares)	109,767
Options, exercisable (in shares)	109,767
Share-Based Payment Arrangement, Option, Exercise Price Range, Lower Range Limit (in dollars per share)	$ 4.1
Share-Based Payment Arrangement, Option, Exercise Price Range, Upper Range Limit (in dollars per share)	$ 10.01