XML 52 R80.htm IDEA: XBRL DOCUMENT
v3.20.1

Other Long-Term Liabilities - Segmented Asset Retirement Obligations (Details) - CAD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | --- | --- | ---
Disclosure of operating segments [line items] |  |  |  |
Asset retirement obligations | $ 5,771 | $ 3,886 | $ 4,327 | $ 3,243
North America |  |  |  |
Disclosure of operating segments [line items] |  |  |  |
Asset retirement obligations | 2,792 | 1,665 |  |
North Sea |  |  |  |
Disclosure of operating segments [line items] |  |  |  |
Asset retirement obligations | 816 | 707 |  |
Offshore Africa |  |  |  |
Disclosure of operating segments [line items] |  |  |  |
Asset retirement obligations | 161 | 134 |  |
Oil Sands Mining and Upgrading |  |  |  |
Disclosure of operating segments [line items] |  |  |  |
Asset retirement obligations | 2,000 | 1,379 |  |
Midstream and Refining |  |  |  |
Disclosure of operating segments [line items] |  |  |  |
Asset retirement obligations | $ 2 | $ 1 |  |

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_DisclosureOfOperatingSegmentsLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of provision for costs related to decommissioning, restoration and rehabilitation. [Refer: Other provisions] + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 37 -IssueDate 2019-01-01 -Section D Examples: disclosures -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=37&code=ifrs-tx-2019-en-r&doctype=Illustrative%20Examples&dita_xref=IAS37_IE_D_TI -URIDate 2019-03-27 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 37 -IssueDate 2019-01-01 -Paragraph 87 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=37&code=ifrs-tx-2019-en-r&anchor=para_87&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_ProvisionForDecommissioningRestorationAndRehabilitationCosts
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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

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

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