XML 107 R77.htm IDEA: XBRL DOCUMENT
v3.8.0.1

INCOME TAXES - Summary of Major Temporary Differences (Details) - CAD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | --- | --- | ---
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |  |
Deferred income tax liabilities | $ 12,859 | $ 10,670 |  |
Deferred income tax assets | (1,884) | (1,597) |  |
Net deferred income tax liability | 10,975 | 9,073 | $ 9,344 | $ 8,970
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 liabilities | 12,484 | 10,259 |  |
Unrealized risk management activities |  |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |  |
Deferred income tax liabilities | 20 | 62 |  |
PRT deduction for corporate income tax |  |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |  |
Deferred income tax liabilities | 7 | 29 |  |
Investments |  |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |  |
Deferred income tax liabilities | 96 | 98 |  |
Investment in North West Redwater Partnership |  |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |  |
Deferred income tax liabilities | 252 | 222 |  |
Asset retirement obligations |  |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |  |
Deferred income tax assets | (1,264) | (983) |  |
Loss carryforwards |  |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |  |
Deferred income tax assets | (523) | (390) |  |
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 assets | (29) | (149) |  |
Deferred PRT |  |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |  |
Deferred income tax assets | (18) | (73) |  |
Other |  |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |  |
Deferred income tax assets | $ (50) | $ (2) |  |

X
- Definition The amounts of income taxes recoverable in future periods in respect of: (a) deductible temporary differences; (b) the carryforward of unused tax losses; and (c) the carryforward of unused tax credits. [Refer: Temporary differences [member]; Unused tax credits [member]; Unused tax losses [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2017-01-01 -Paragraph 81 -Subparagraph g -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_g_i&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 54 -Subparagraph o -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_54_o&doctype=Standard -URIDate 2017-03-09 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 56 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_56&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_DeferredTaxAssets
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amounts of income taxes payable in future periods in respect of taxable temporary differences. [Refer: Temporary differences [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2017-01-01 -Paragraph 81 -Subparagraph g -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_g_i&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 54 -Subparagraph o -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_54_o&doctype=Standard -URIDate 2017-03-09 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 56 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_56&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_DeferredTaxLiabilities
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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 2017-01-01 -Paragraph 81 -Subparagraph g -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_g_i&doctype=Standard -URIDate 2017-03-09 + Details
Name: | ifrs-full_DeferredTaxLiabilityAsset
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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_UnrealisedRiskManagementActivitiesRelatedTemporaryDifferencesMember
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=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_DecommissioningRestorationAndRehabilitationCostsRelatedTemporaryDifferencesMember
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=ifrs-full_UnrealisedForeignExchangeGainsLossesMember
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=ifrs-full_OtherTemporaryDifferencesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |