XML 121 R92.htm IDEA: XBRL DOCUMENT v3.19.1

NET EARNINGS (LOSS) PER COMMON SHARE - Narrative (Details) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Earnings per share [abstract]
Potentially anti-dilutive securities (in shares)	23,458,000	17,547,000

X

- Definition

Antidilutive Securities Excluded From Computation Of Earnings Per Share, Amount1

+ References

No definition available.

+ Details

Name:	cnq_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount1
Namespace Prefix:	cnq_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- References

No definition available.

+ Details

Name:	ifrs-full_EarningsPerShareAbstract
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration