XML 129 R90.htm IDEA: XBRL DOCUMENT
v3.25.3

Income taxes - Disclosure of the continuity of deferred tax balances (Details) - CAD ($) $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2025 | Sep. 30, 2024
Reconciliation of changes in deferred tax liability (asset) [abstract] |  |
Beginning balance | $ 221,435 | $ 74,351
Additions from business acquisitions | (45,392) | 0
Recognized in earnings | (626) | 146,100
Recognized in other comprehensive income | (7,474) | 1,556
Recognized in equity | (5,811) | (3,599)
Foreign currency translation adjustment and other | 5,479 | 3,027
Ending balance | 167,611 | 221,435
Accounts payable, accrued compensation and liabilities, provisions, and other long-term liabilities |  |
Reconciliation of changes in deferred tax liability (asset) [abstract] |  |
Beginning balance | 132,021 | 112,599
Additions from business acquisitions | 0 | 0
Recognized in earnings | (13,894) | 20,946
Recognized in other comprehensive income | 0 | 0
Recognized in equity | (5,811) | (3,599)
Foreign currency translation adjustment and other | 3,933 | 2,075
Ending balance | 116,249 | 132,021
Tax benefits on losses carried forward |  |
Reconciliation of changes in deferred tax liability (asset) [abstract] |  |
Beginning balance | 51,180 | 56,078
Additions from business acquisitions | 0 | 0
Recognized in earnings | 618 | (7,265)
Recognized in other comprehensive income | 0 | 0
Recognized in equity | 0 | 0
Foreign currency translation adjustment and other | 2,164 | 2,367
Ending balance | 53,962 | 51,180
Retirement benefits obligations |  |
Reconciliation of changes in deferred tax liability (asset) [abstract] |  |
Beginning balance | 27,034 | 27,243
Additions from business acquisitions | 0 | 0
Recognized in earnings | 2,297 | 795
Recognized in other comprehensive income | (13,062) | (356)
Recognized in equity | 0 | 0
Foreign currency translation adjustment and other | 2,125 | (648)
Ending balance | 18,394 | 27,034
Capitalized research and development |  |
Reconciliation of changes in deferred tax liability (asset) [abstract] |  |
Beginning balance | 174,467 | 92,880
Additions from business acquisitions | 0 | 0
Recognized in earnings | 18,545 | 82,302
Recognized in other comprehensive income | 0 | 0
Recognized in equity | 0 | 0
Foreign currency translation adjustment and other | 5,370 | (715)
Ending balance | 198,382 | 174,467
Lease liabilities |  |
Reconciliation of changes in deferred tax liability (asset) [abstract] |  |
Beginning balance | 156,479 | 169,288
Additions from business acquisitions | 4,360 | 0
Recognized in earnings | (712) | (16,919)
Recognized in other comprehensive income | 0 | 0
Recognized in equity | 0 | 0
Foreign currency translation adjustment and other | 7,925 | 4,110
Ending balance | 168,052 | 156,479
PP&E, contract costs, intangible assets and other long-term assets |  |
Reconciliation of changes in deferred tax liability (asset) [abstract] |  |
Beginning balance | (73,149) | (123,717)
Additions from business acquisitions | (44,860) | 0
Recognized in earnings | (4,353) | 49,457
Recognized in other comprehensive income | 0 | 0
Recognized in equity | 0 | 0
Foreign currency translation adjustment and other | (4,801) | 1,111
Ending balance | (127,163) | (73,149)
Right-of-use assets |  |
Reconciliation of changes in deferred tax liability (asset) [abstract] |  |
Beginning balance | (123,982) | (143,411)
Additions from business acquisitions | (4,360) | 0
Recognized in earnings | 3,237 | 23,077
Recognized in other comprehensive income | 0 | 0
Recognized in equity | 0 | 0
Foreign currency translation adjustment and other | (6,800) | (3,648)
Ending balance | (131,905) | (123,982)
Work in progress |  |
Reconciliation of changes in deferred tax liability (asset) [abstract] |  |
Beginning balance | (15,621) | (14,372)
Additions from business acquisitions | 0 | 0
Recognized in earnings | (3,593) | (926)
Recognized in other comprehensive income | 0 | 0
Recognized in equity | 0 | 0
Foreign currency translation adjustment and other | (857) | (323)
Ending balance | (20,071) | (15,621)
Goodwill |  |
Reconciliation of changes in deferred tax liability (asset) [abstract] |  |
Beginning balance | (93,682) | (87,259)
Additions from business acquisitions | 0 | 0
Recognized in earnings | (20,157) | (6,346)
Recognized in other comprehensive income | 0 | 0
Recognized in equity | 0 | 0
Foreign currency translation adjustment and other | (2,949) | (77)
Ending balance | (116,788) | (93,682)
Refundable tax credits on salaries |  |
Reconciliation of changes in deferred tax liability (asset) [abstract] |  |
Beginning balance | (24,943) | (22,568)
Additions from business acquisitions | (532) | 0
Recognized in earnings | 6,257 | (2,478)
Recognized in other comprehensive income | 0 | 0
Recognized in equity | 0 | 0
Foreign currency translation adjustment and other | (25) | 103
Ending balance | (19,243) | (24,943)
Cash flow and net investment hedges |  |
Reconciliation of changes in deferred tax liability (asset) [abstract] |  |
Beginning balance | 14,060 | (4,010)
Additions from business acquisitions | 0 | 0
Recognized in earnings | 26 | 14,164
Recognized in other comprehensive income | 5,873 | 5,374
Recognized in equity | 0 | 0
Foreign currency translation adjustment and other | 294 | (1,468)
Ending balance | 20,253 | 14,060
Other |  |
Reconciliation of changes in deferred tax liability (asset) [abstract] |  |
Beginning balance | (2,429) | 11,600
Additions from business acquisitions | 0 | 0
Recognized in earnings | 11,103 | (10,707)
Recognized in other comprehensive income | (285) | (3,462)
Recognized in equity | 0 | 0
Foreign currency translation adjustment and other | (900) | 140
Ending balance | $ 7,489 | $ (2,429)

X
- References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2025-01-01 -Paragraph 81 -Subparagraph g -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2025-en-r&anchor=para_81_g_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 f -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_f_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 f -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_f_ii&doctype=Standard -URIDate 2025-03-27 + Details
Name: | ifrs-full_DeferredTaxExpenseIncomeRecognisedInProfitOrLoss
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of deferred tax liabilities or assets. [Refer: Deferred tax liabilities; Deferred tax assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2025-01-01 -Paragraph 81 -Subparagraph g -Clause i -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2025-en-r&anchor=para_81_g_i&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 f -Clause i -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_f_i&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 f -Clause i -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_f_i&doctype=Standard -URIDate 2025-03-27 + Details
Name: | ifrs-full_DeferredTaxLiabilityAsset
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of deferred tax related to items credited (charged) directly to equity. [Refer: Deferred tax expense (income)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2025-01-01 -Paragraph 81 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2025-en-r&anchor=para_81_a&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 a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_a&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 a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_a&doctype=Standard -URIDate 2025-03-27 + Details
Name: | ifrs-full_DeferredTaxRelatingToItemsChargedOrCreditedDirectlyToEquity
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of income tax relating to amounts recognised in other comprehensive income. [Refer: Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2025-01-01 -Paragraph 81 -Subparagraph ab -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2025-en-r&anchor=para_81_ab&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 b -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_b&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 b -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_194_b&doctype=Standard -URIDate 2025-03-27 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Note Expiry date 2027-01-01 -Name IAS -Number 1 -IssueDate 2025-01-01 -Paragraph 90 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_90&doctype=Standard -URIDate 2025-03-27 + Details
Name: | ifrs-full_IncomeTaxRelatingToComponentsOfOtherComprehensiveIncome
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition The increase (decrease) in deferred tax liability (asset) resulting from business combinations. [Refer: Deferred tax liability (asset)] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 12 -IssueDate 2025-01-01 -Paragraph 81 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2025-en-r&anchor=para_81&doctype=Standard -URIDate 2025-03-27 + Details
Name: | ifrs-full_IncreaseDecreaseThroughBusinessCombinationsDeferredTaxLiabilityAsset
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The increase (decrease) in deferred tax liability (asset) resulting from the net exchange differences arising when the financial statements are translated from the functional currency into a different presentation currency, including the translation of a foreign operation into the presentation currency of the reporting entity. [Refer: Deferred tax liability (asset)] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 12 -IssueDate 2025-01-01 -Paragraph 81 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2025-en-r&anchor=para_81&doctype=Standard -URIDate 2025-03-27 + Details
Name: | ifrs-full_IncreaseDecreaseThroughNetExchangeDifferencesDeferredTaxLiabilityAsset
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | ifrs-full_ReconciliationOfChangesInDeferredTaxLiabilityAssetAbstract
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=gib_AccountsPayableAndAccruedCompensationAndLiabilitiesProvisionsAndOtherLongTermLiabilitiesRelatedTemporaryDifferenceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=gib_TaxBenefitsOnLossesCarriedForwardRelatedTemporaryDifferenceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=gib_RetirementBenefitsObligationsRelatedTemporaryDifferenceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=gib_CapitalizedResearchAndDevelopmentRelatedTemporaryDifferenceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=ifrs-full_LeaseLiabilitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=gib_PropertyPlantAndEquipmentContractCostsIntangibleAssetsAndOtherLongTermAssetsRelatedTemporaryDifferenceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=ifrs-full_RightofuseAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=gib_WorkInProgressRelatedTemporaryDifferenceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=gib_GoodwillRelatedTemporaryDifferenceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=gib_RefundableTaxCreditsOnSalariesRelatedTemporaryDifferenceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=gib_CashFlowAndNetInvestmentHedgesRelatedTemporaryDifferenceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=ifrs-full_OtherTemporaryDifferencesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |