XML 129 R100.htm IDEA: XBRL DOCUMENT v3.19.1

FINANCIAL INSTRUMENTS - Foreign currency exchange rate risk management (Details)	12 Months Ended
	Dec. 31, 2018 USD ($) $ / $
Foreign currency exchange rate risk | Cash flow hedges | Forward contracts
Disclosure of detailed information about hedging instruments [line items]
Notional amount	$ 3,058,000,000
US
Disclosure of detailed information about hedging instruments [line items]
Exchange rate (US$/C$)	1.00
Cross currency swaps | Foreign currency exchange rate risk | Cash flow hedges | Currency swap contract, term through November 2021
Disclosure of detailed information about hedging instruments [line items]
Amount	500,000,000
Exchange rate (US$/C$) | $ / $	1.022
Cross currency swaps | Foreign currency exchange rate risk | Cash flow hedges | Currency swap contract, term through March 2038
Disclosure of detailed information about hedging instruments [line items]
Amount	550,000,000
Exchange rate (US$/C$) | $ / $	1.170
Cross currency swaps | US | Foreign currency exchange rate risk | Cash flow hedges | Currency swap contract, term through November 2021
Disclosure of detailed information about hedging instruments [line items]
Interest rate	3.45%
Cross currency swaps | US | Foreign currency exchange rate risk | Cash flow hedges | Currency swap contract, term through March 2038
Disclosure of detailed information about hedging instruments [line items]
Interest rate	6.25%
Cross currency swaps | CAD | Foreign currency exchange rate risk | Cash flow hedges | Currency swap contract, term through November 2021
Disclosure of detailed information about hedging instruments [line items]
Interest rate	3.96%
Cross currency swaps | CAD | Foreign currency exchange rate risk | Cash flow hedges | Currency swap contract, term through March 2038
Disclosure of detailed information about hedging instruments [line items]
Interest rate	5.76%
Forward contracts | Foreign currency exchange rate risk
Disclosure of detailed information about hedging instruments [line items]
Notional amount	$ 3,506,000,000
Derivative, term of contract	90 days

X

- Definition

Derivative, Term Of Contract1

+ References

No definition available.

+ Details

Name:	cnq_DerivativeTermOfContract1
Namespace Prefix:	cnq_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The average exchange rate used by the entity. Exchange rate is the ratio of exchange for two currencies.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_112_c&doctype=Standard
-URIDate 2018-03-16

+ Details

Name:	ifrs-full_AverageForeignExchangeRate
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The average rate of a hedging instrument. [Refer: Hedging instruments [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 23B
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_23B_b&doctype=Standard
-URIDate 2018-03-16

+ Details

Name:	ifrs-full_AverageRateOfHedgingInstrument
Namespace Prefix:	ifrs-full_
Data Type:	num:percentItemType
Balance Type:	na
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_DisclosureOfDetailedInformationAboutHedgingInstrumentsLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The nominal amount of a hedging instrument. [Refer: Hedging instruments [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 23B
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_23B_a&doctype=Standard
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 24A
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_24A_d&doctype=Standard
-URIDate 2018-03-16

+ Details

Name:	ifrs-full_NominalAmountOfHedgingInstrument
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

Name:	invest_DerivativeNotionalAmount
Namespace Prefix:	invest_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

X

- Details

Name:	ifrs-full_TypesOfRisksAxis=ifrs-full_CurrencyRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_TypesOfHedgesAxis=ifrs-full_CashFlowHedgesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_HedgingInstrumentsAxis=ifrs-full_ForwardContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CurrencyAxis=currency_USD
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_ClassesOfFinancialInstrumentsAxis=ifrs-full_CurrencySwapContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_HedgingInstrumentsAxis=cnq_CurrencySwapContractTermThroughNovember2021Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_HedgingInstrumentsAxis=cnq_CurrencySwapContractTermThroughMarch2038Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_CurrencyAxis=currency_CAD
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_ClassesOfFinancialInstrumentsAxis=ifrs-full_ForwardContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: