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

The number of other equity instruments (ie other than share options) granted in a share-based payment arrangement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 47
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_47_b&doctype=Standard
-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 45
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_45&doctype=Standard
-URIDate 2017-03-09

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

The number of other equity instruments (ie other than share options) outstanding in a share-based payment arrangement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 45
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_45&doctype=Standard
-URIDate 2017-03-09

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

The number of other equity instruments (ie other than share options) forfeited and expired in a share-based payment arrangement.

No definition available.

Name:	su_NumberOfOtherEquityInstrumentsForfeitedAndExpiredInShareBasedPaymentArrangement
Namespace Prefix:	su_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

The number of other equity instruments (ie other than share options) redeemed for cash in a share-based payment arrangement.

No definition available.

Name:	su_NumberOfOtherEquityInstrumentsRedeemedForCashInShareBasedPaymentArrangement
Namespace Prefix:	su_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

The percentage of share price receivable at the time of vesting of share units.

No definition available.

Name:	su_PercentageOfSharePriceEntitleToReceiveAtTimeOfVesting
Namespace Prefix:	su_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The fourth incremental percentage of share price receivable by the executives at the time of vesting of share units.

No definition available.

Name:	su_PercentageOfSharePriceEntitleToReceiveAtTimeOfVestingIncrementsFour
Namespace Prefix:	su_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The first incremental percentage of share price receivable by the executives at the time of vesting of share units.

No definition available.

Name:	su_PercentageOfSharePriceEntitleToReceiveAtTimeOfVestingIncrementsOne
Namespace Prefix:	su_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The third incremental percentage of share price receivable by the executives at the time of vesting of share units.

No definition available.

Name:	su_PercentageOfSharePriceEntitleToReceiveAtTimeOfVestingIncrementsThree
Namespace Prefix:	su_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The second incremental percentage of share price receivable by the executives at the time of vesting of share units.

No definition available.

Name:	su_PercentageOfSharePriceEntitleToReceiveAtTimeOfVestingIncrementsTwo
Namespace Prefix:	su_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The vesting life of awards in a share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	su_VestingLifeOfShareBasedAwards
Namespace Prefix:	su_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Name:	ifrs-full_TypesOfSharebasedPaymentArrangementsAxis=us-gaap_PerformanceSharesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_RangeAxis=ifrs-full_BottomOfRangeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_RangeAxis=ifrs-full_TopOfRangeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_TypesOfSharebasedPaymentArrangementsAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_TypesOfSharebasedPaymentArrangementsAxis=su_DeferredShareUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_CategoriesOfRelatedPartiesAxis=us-gaap_DirectorMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: