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Income taxes - Reconciliation of effective income tax rate from the combined federal and provincial Canadian statutory tax rate (Details) | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024
Income Taxes [Abstract] |  |
Company's statutory tax rate | 26.50% | 26.50%
Effect of foreign tax rate differences | (0.70%) | (0.30%)
Final determination from agreements with tax authorities and expirations of statutes of limitations | (0.40%) | (0.30%)
Non-deductible and tax exempt items | 0.50% | 0.30%
Recognition of previously unrecognized temporary differences | 0.00% | (0.30%)
Minimum income tax charge | 0.20% | 0.20%
Changes in tax laws and rates | (0.10%) | 0.00%
Effective income tax rate | 26.00% | 26.10%

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- Definition Tax Rate Effect Of Expense Not Deductible In Determining Taxable Profit (Loss) And Revenues Exempt From Taxation + References No definition available. + Details
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- Definition The applicable income tax rate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2025-01-01 -Paragraph 81 -Subparagraph c -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2025-en-r&anchor=para_81_c_ii&doctype=Standard -URIDate 2025-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2027-01-01 -Name IFRS -Number 19 -IssueDate 2025-01-01 -Paragraph 194 -Subparagraph c -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_c_ii&doctype=Standard -URIDate 2025-03-27 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2027-01-01 -Name IFRS -Number 19 -IssueDate 2025-01-01 -Paragraph 194 -Subparagraph c -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_c_ii&doctype=Standard -URIDate 2025-03-27 + Details
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- Definition The tax expense (income) divided by the accounting profit. [Refer: Accounting profit] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2025-01-01 -Paragraph 81 -Subparagraph c -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2025-en-r&anchor=para_81_c_ii&doctype=Standard -URIDate 2025-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2027-01-01 -Name IFRS -Number 19 -IssueDate 2025-01-01 -Paragraph 194 -Subparagraph c -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_c_ii&doctype=Standard -URIDate 2025-03-27 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2027-01-01 -Name IFRS -Number 19 -IssueDate 2025-01-01 -Paragraph 194 -Subparagraph c -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_c_ii&doctype=Standard -URIDate 2025-03-27 + Details
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- Definition The tax rate effect on the reconciliation between the average effective tax rate and the applicable tax rate resulting from a change in tax rate. [Refer: Average effective tax rate; Applicable tax rate] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2025-01-01 -Paragraph 81 -Subparagraph c -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2025-en-r&anchor=para_81_c_ii&doctype=Standard -URIDate 2025-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2027-01-01 -Name IFRS -Number 19 -IssueDate 2025-01-01 -Paragraph 194 -Subparagraph c -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_c_ii&doctype=Standard -URIDate 2025-03-27 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2027-01-01 -Name IFRS -Number 19 -IssueDate 2025-01-01 -Paragraph 194 -Subparagraph c -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_c_ii&doctype=Standard -URIDate 2025-03-27 + Details
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- Definition The tax rate effect on the reconciliation between the average effective tax rate and the applicable tax rate resulting from the application of foreign tax rates. [Refer: Average effective tax rate; Applicable tax rate] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2025-01-01 -Paragraph 81 -Subparagraph c -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2025-en-r&anchor=para_81_c_ii&doctype=Standard -URIDate 2025-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2027-01-01 -Name IFRS -Number 19 -IssueDate 2025-01-01 -Paragraph 194 -Subparagraph c -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_c_ii&doctype=Standard -URIDate 2025-03-27 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2027-01-01 -Name IFRS -Number 19 -IssueDate 2025-01-01 -Paragraph 194 -Subparagraph c -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_c_ii&doctype=Standard -URIDate 2025-03-27 + Details
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