Share-based payments - Disclosure of weighted average assumptions used in the calculation of fair value of stock options (Details)	12 Months Ended
Sep. 30, 2023 CAD ($) year $ / shares	Sep. 30, 2022 CAD ($) year $ / shares
Share-Based Payment Arrangements [Abstract]
Grant date fair value (in CAD per share) \| $	$ 0	$ 20.94
Dividend yield (%)	0.00%	0.00%
Expected volatility (%)	0.00%	21.27%
Risk-free interest rate (%)	0.00%	1.28%
Expected life (years) \| year	0	4.00
Exercise price (in CAD per share)	$ 0	$ 110.10
Share price (in CAD per share)	$ 0	$ 110.10

Share-Based Payment Arrangements [Abstract]

No definition available.

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- Definition

The expected volatility of the share price used to calculate the fair value of the share options granted. Expected volatility is a measure of the amount by which a price is expected to fluctuate during a period. The measure of volatility used in option pricing models is the annualised standard deviation of the continuously compounded rates of return on the share over a period of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2023-01-01
-Paragraph 47
-Subparagraph a
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2023-en-r&anchor=para_47_a_i&doctype=Standard
-URIDate 2023-03-23

+ Details

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- Definition

The option life of share options granted.

+ References

+ Details

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- Definition

The implied yield currently available on zero-coupon government issues of the country in whose currency the exercise price for share options granted is expressed, with a remaining term equal to the expected term of the option being valued (based on the option's remaining contractual life and taking into account the effects of expected early exercise). [Refer: Government [member]]

+ References

+ Details

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- Definition

The exercise price of share options granted.

+ References

+ Details

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- Definition

The percentage of an expected dividend used to calculate the fair value of share options granted.

+ References

+ Details

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- Definition

The weighted average fair value of share options granted during the period at the measurement date. [Refer: Weighted average [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2023-01-01
-Paragraph 47
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2023-en-r&anchor=para_47_a&doctype=Standard
-URIDate 2023-03-23

+ Details

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- Definition

The weighted average share price used as input to the option pricing model to calculate the fair value of share options granted. [Refer: Option pricing model [member]; Weighted average [member]]

+ References

+ Details

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