XML 157 R86.htm IDEA: XBRL DOCUMENT
v3.20.1

Income Taxes - Summary of Movements in Deferred Tax Assets and Liabilities (Details) - CAD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred income tax (recovery) expense | $ (894) | $ 557 | $ 640
Property, plant and equipment and exploration and evaluation assets |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred income tax (recovery) expense | (775) | 281 | 541
Lease assets |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred income tax (recovery) expense | 414 | 0 | 0
Unrealized foreign exchange loss (gain) on long-term debt |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred income tax (recovery) expense | 55 | (75) | 120
Unrealized risk management activities |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred income tax (recovery) expense | (14) | 18 | (46)
Asset retirement obligations |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred income tax (recovery) expense | (317) | 175 | (88)
Lease liabilities |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred income tax (recovery) expense | (418) |  |
Share-based compensation |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred income tax (recovery) expense | (11) | (5) | 0
Loss carryforwards |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred income tax (recovery) expense | 170 | (61) | 48
Investments |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred income tax (recovery) expense | (10) | (50) | (2)
Investment in North West Redwater Partnership |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred income tax (recovery) expense | 179 | 162 | 30
Deferred PRT |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred income tax (recovery) expense | 1 | 17 | 54
PRT deduction for corporate income tax |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred income tax (recovery) expense | 0 | (7) | (21)
Other |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred income tax (recovery) expense | $ (168) | $ 102 | $ 4

X
- Definition The amount of tax expense or income relating to changes in deferred tax liabilities and deferred tax assets, recognised in profit or loss. [Refer: Deferred tax assets; Deferred tax expense (income); Deferred tax liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2019-01-01 -Paragraph 81 -Subparagraph g -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2019-en-r&anchor=para_81_g_ii&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_DeferredTaxExpenseIncomeRecognisedInProfitOrLoss
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
Name: | ifrs-full_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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

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

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

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

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

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

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

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

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

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=cnq_PetroleumRevenueTaxDeductionForCorporateIncomeTaxRelatedTemporaryDifferencesMember
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: |