Segmented information - Disclosure of revenue information based on services provided by the Company (Details) - CAD ($) $ in Thousands	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Disclosure of products and services [line items]
Revenue	$ 12,867,201	$ 12,126,793
Managed IT and business process services
Disclosure of products and services [line items]
Revenue	6,980,988	6,722,967
Business and strategic IT consulting and systems integration services
Disclosure of products and services [line items]
Revenue	$ 5,886,213	$ 5,403,826

The income arising in the course of an entity's ordinary activities. Income is increases in assets, or decreases in liabilities, that result in increases in equity, other than those relating to contributions from holders of equity claims.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2021-01-01
-Paragraph 28
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_28_a&doctype=Standard
-URIDate 2021-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2021-01-01
-Paragraph 23
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_23_a&doctype=Standard
-URIDate 2021-03-24

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2021-01-01
-Paragraph 32
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_32&doctype=Standard
-URIDate 2021-03-24

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2021-01-01
-Paragraph 33
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_33_a&doctype=Standard
-URIDate 2021-03-24

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2021-01-01
-Paragraph 34
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_34&doctype=Standard
-URIDate 2021-03-24

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 82
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_82_a&doctype=Standard
-URIDate 2021-03-24

Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 103
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_103&doctype=Standard
-URIDate 2021-03-24

Reference 8: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 102
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_102&doctype=Standard
-URIDate 2021-03-24

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 5
-IssueDate 2021-01-01
-Paragraph 33
-Subparagraph b
-Clause i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=5&code=ifrs-tx-2021-en-r&anchor=para_33_b_i&doctype=Standard
-URIDate 2021-03-24

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2021-01-01
-Paragraph B12
-Subparagraph b
-Clause v
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2021-en-r&anchor=para_B12_b_v&doctype=Appendix&subtype=B
-URIDate 2021-03-24

Reference 11: http://www.xbrl.org/2003/role/exampleRef
-Name IFRS
-Number 12
-IssueDate 2021-01-01
-Paragraph B10
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2021-en-r&anchor=para_B10_b&doctype=Appendix&subtype=B
-URIDate 2021-03-24

+ Details