XML 87 R60.htm IDEA: XBRL DOCUMENT
v3.20.1

Exploration and Evaluation Assets - Narrative (Details) $ in Millions, $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 CAD ($) | Dec. 31, 2018 USD ($) agreement | Dec. 31, 2018 CAD ($) agreement | Dec. 31, 2017 CAD ($) | Jun. 27, 2019 CAD ($)
Disclosure Of Detailed Information About Exploration For And Evaluation Of Mineral Resources [Line Items] |  |  |  |  |
Disposals of exploration and evaluation assets |  |  | $ 100 |  |
Proceeds from disposal of exploration and evaluation assets | $ 0 |  | $ 16 | $ 35 |
Farm-out agreements, working interest retained |  | 20.00% | 20.00% |  |
Oil Sands Mining and Upgrading |  |  |  |  |
Disclosure Of Detailed Information About Exploration For And Evaluation Of Mineral Resources [Line Items] |  |  |  |  |
Disposals of exploration and evaluation assets |  |  | $ 7 |  |
North America |  |  |  |  |
Disclosure Of Detailed Information About Exploration For And Evaluation Of Mineral Resources [Line Items] |  |  |  |  |
Exploration and evaluation assets |  |  |  | 27 |
Asset retirement obligations | $ 20 |  | 13 | 63 |
Disposals of exploration and evaluation assets |  |  | 4 | 1 |
Proceeds from disposal of exploration and evaluation assets |  |  |  | 36 |
Gain on sale of exploration and evaluation assets |  |  | $ 16 | $ 35 |
Offshore Africa |  |  |  |  |
Disclosure Of Detailed Information About Exploration For And Evaluation Of Mineral Resources [Line Items] |  |  |  |  |
Number of farm-out agreements | agreement |  | 2 | 2 |  |
Disposals of exploration and evaluation assets |  |  | $ 89 |  |
Devon |  |  |  |  |
Disclosure Of Detailed Information About Exploration For And Evaluation Of Mineral Resources [Line Items] |  |  |  |  |
Total purchase consideration |  |  |  |  | $ 3,412
Exploration and evaluation assets |  |  |  |  | 91
Property, plant and equipment |  |  |  |  | 3,325
Asset retirement obligations |  |  |  |  | $ 178
Laricina Energy Ltd | North America |  |  |  |  |
Disclosure Of Detailed Information About Exploration For And Evaluation Of Mineral Resources [Line Items] |  |  |  |  |
Total purchase consideration |  |  | 46 |  |
Exploration and evaluation assets |  |  | 118 |  |
Property, plant and equipment |  |  | 44 |  |
Cash |  |  | 24 |  |
Deferred tax assets recognised as of acquisition date |  |  | 168 |  |
Net working capital liabilities recognised as of acquisition date |  |  | 18 |  |
Asset retirement obligations |  |  | 17 |  |
Notes payable recognised as of acquisition date |  |  | 48 |  |
Gain recognised on acquisition, pre-tax |  |  | $ 225 |  |
Farm-Out Agreements, Offshore Africa | Offshore Africa |  |  |  |  |
Disclosure Of Detailed Information About Exploration For And Evaluation Of Mineral Resources [Line Items] |  |  |  |  |
Farm-out agreements, working interest disposed |  | 30.00% | 30.00% |  |
Disposals of exploration and evaluation assets |  |  | $ 89 |  |
Disposals of exploration and evaluation assets, costs incurred in past fiscal year recovered |  |  | 14 |  |
Proceeds from disposal of exploration and evaluation assets |  | $ 79 | 105 |  |
Gain recognised on farm-out, pre-tax |  |  | 16 |  |
Gain recognised on farm-out, after-tax |  |  | 12 |  |
Joslyn Oil Sands Project | Oil Sands Mining and Upgrading |  |  |  |  |
Disclosure Of Detailed Information About Exploration For And Evaluation Of Mineral Resources [Line Items] |  |  |  |  |
Asset acquisition, exploration and evaluation assets |  |  | 222 |  |
Asset acquisition, asset retirement obligations |  |  | 4 |  |
Asset acquisition, total purchase consideration |  |  | 218 |  |
Asset acquisition, cash transferred |  |  | $ 100 |  |

X
- Definition Asset Acquisition, Cash Transferred + References No definition available. + Details
Name: | cnq_AssetAcquisitionCashTransferred
Namespace Prefix: | cnq_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Asset Acquisition, Consideration Transferred, Acquisition-Date Fair Value + References No definition available. + Details
Name: | cnq_AssetAcquisitionConsiderationTransferredAcquisitionDateFairValue
Namespace Prefix: | cnq_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Asset Acquisition, Decommissioning, Restoration, And Rehabilitation Assets Recognized As of Acquisition Date + References No definition available. + Details
Name: | cnq_AssetAcquisitionDecommissioningRestorationAndRehabilitationAssetsRecognizedAsofAcquisitionDate
Namespace Prefix: | cnq_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Asset Acquisition, Exploration And Evaluation Assets Recognized As Of Acquisition Date + References No definition available. + Details
Name: | cnq_AssetAcquisitionExplorationAndEvaluationAssetsRecognizedAsOfAcquisitionDate
Namespace Prefix: | cnq_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Decommissioning, Restoration, And Rehabilitation Assets Recognized As of Acquisition Date + References No definition available. + Details
Name: | cnq_DecommissioningRestorationAndRehabilitationAssetsRecognizedAsofAcquisitionDate
Namespace Prefix: | cnq_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition [Line Items] for Disclosure Of Detailed Information About Exploration For And Evaluation Of Mineral Resources [Table] + References No definition available. + Details
Name: | cnq_DisclosureOfDetailedInformationAboutExplorationForAndEvaluationOfMineralResourcesLineItems
Namespace Prefix: | cnq_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Disposals, Exploration For And Evaluation Of Mineral Resources + References No definition available. + Details
Name: | cnq_DisposalsExplorationForAndEvaluationOfMineralResources
Namespace Prefix: | cnq_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Disposals, Exploration For And Evaluation Of Mineral Resources, Costs Incurred In Past Fiscal Year Recovered + References No definition available. + Details
Name: | cnq_DisposalsExplorationForAndEvaluationOfMineralResourcesCostsIncurredInPastFiscalYearRecovered
Namespace Prefix: | cnq_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Exploration And Evaluation Assets Recognized As Of Acquisition Date + References No definition available. + Details
Name: | cnq_ExplorationAndEvaluationAssetsRecognizedAsOfAcquisitionDate
Namespace Prefix: | cnq_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Gain Recognised On Acquisition, Pre-Tax + References No definition available. + Details
Name: | cnq_GainRecognisedOnAcquisitionPreTax
Namespace Prefix: | cnq_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Gain Recognised On Disposal, After-Tax + References No definition available. + Details
Name: | cnq_GainRecognisedOnDisposalAfterTax
Namespace Prefix: | cnq_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Gain Recognised On Disposal, Pre-Tax + References No definition available. + Details
Name: | cnq_GainRecognisedOnDisposalPreTax
Namespace Prefix: | cnq_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Gains (Losses) On Disposals Of Exploration And Evaluation Assets + References No definition available. + Details
Name: | cnq_GainsLossesOnDisposalsOfExplorationAndEvaluationAssets
Namespace Prefix: | cnq_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Net Working Capital Liabilities Recognised As Of Acquisition Date + References No definition available. + Details
Name: | cnq_NetWorkingCapitalLiabilitiesRecognisedAsOfAcquisitionDate
Namespace Prefix: | cnq_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Number Of Farm-Out Agreements + References No definition available. + Details
Name: | cnq_NumberOfFarmOutAgreements
Namespace Prefix: | cnq_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Working Interest Disposed + References No definition available. + Details
Name: | cnq_WorkingInterestDisposed
Namespace Prefix: | cnq_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Working Interest Retained + References No definition available. + Details
Name: | cnq_WorkingInterestRetained
Namespace Prefix: | cnq_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The fair value, at acquisition date, of the consideration transferred in a business combination. [Refer: Business combinations [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 3 -IssueDate 2019-01-01 -Paragraph B64 -Subparagraph f -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2019-en-r&anchor=para_B64_f&doctype=Appendix&subtype=B -URIDate 2019-03-27 + Details
Name: | ifrs-full_AcquisitiondateFairValueOfTotalConsiderationTransferred
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount recognised as of the acquisition date for borrowings assumed in a business combination. [Refer: Borrowings; Business combinations [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 3 -IssueDate 2019-01-01 -Paragraph B64 -Subparagraph i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2019-en-r&anchor=para_B64_i&doctype=Appendix&subtype=B -URIDate 2019-03-27 + Details
Name: | ifrs-full_BorrowingsRecognisedAsOfAcquisitionDate
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount recognised as of the acquisition date for cash and cash equivalents acquired in a business combination. [Refer: Cash and cash equivalents; Business combinations [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 3 -IssueDate 2019-01-01 -Paragraph B64 -Subparagraph i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2019-en-r&anchor=para_B64_i&doctype=Appendix&subtype=B -URIDate 2019-03-27 + Details
Name: | ifrs-full_CashAndCashEquivalentsRecognisedAsOfAcquisitionDate
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount recognised as of the acquisition date for deferred tax assets acquired in a business combination. [Refer: Deferred tax assets; Business combinations [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 3 -IssueDate 2019-01-01 -Paragraph B64 -Subparagraph i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2019-en-r&anchor=para_B64_i&doctype=Appendix&subtype=B -URIDate 2019-03-27 + Details
Name: | ifrs-full_DeferredTaxAssetsRecognisedAsOfAcquisitionDate
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The cash inflow from the disposal of exploration and evaluation assets. [Refer: Exploration and evaluation assets [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 7 -IssueDate 2019-01-01 -Paragraph 16 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_16&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_ProceedsFromDisposalOfExplorationAndEvaluationAssets
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount recognised as of the acquisition date for plant, property and equipment acquired in a business combination. [Refer: Property, plant and equipment; Business combinations [member]] + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name IFRS -Number 3 -IssueDate 2019-01-01 -Paragraph B64 -Subparagraph i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2019-en-r&anchor=para_B64_i&doctype=Appendix&subtype=B -URIDate 2019-03-27 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Name IFRS -Number 3 -IssueDate 2019-01-01 -Paragraph IE72 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2019-en-r&anchor=para_IE72&doctype=Illustrative%20Examples -URIDate 2019-03-27 + Details
Name: | ifrs-full_PropertyPlantAndEquipmentRecognisedAsOfAcquisitionDate
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | ifrs-full_SegmentsAxis=cnq_OilSandsMiningAndUpgradingSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SegmentsAxis=cnq_NorthAmericaExplorationAndProductionSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SegmentsAxis=cnq_OffshoreAfricaExplorationAndProductionSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_BusinessCombinationsAxis=cnq_DevonCanadaCorporationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_BusinessCombinationsAxis=cnq_LaricinaEnergyLtdMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_BusinessCombinationsAxis=cnq_FarmOutAgreementsOffshoreAfricaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TransactionsRecognisedSeparatelyFromAcquisitionOfAssetsAndAssumptionOfLiabilitiesInBusinessCombinationAxis=cnq_JoslynOilSandsProjectMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |