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Data Type:	xbrli:stringItemType
Balance Type:	na
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The amount of undrawn borrowing facilities that may be available for future operating activities and to settle capital commitments. [Refer: Capital commitments]

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 7
-IssueDate 2017-01-01
-Paragraph 50
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=7&date=2017-03-01&anchor=para_50_a&doctype=Standard
-URIDate 2017-03-09

Name:	ifrs-full_UndrawnBorrowingFacilities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the amount of cash provided towards collateral for credit facilities.

No definition available.

Name:	su_CashCollateralProvidedForCreditFacilities
Namespace Prefix:	su_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Represents the amount of credit facility that was cancelled during the period.

No definition available.

Name:	su_CreditFacilityCancellation
Namespace Prefix:	su_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The amount of decrease in credit facility.

No definition available.

Name:	su_DecreaseInCreditFacility
Namespace Prefix:	su_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents the portion of line of credit facilities that are assigned for specific purposes.

No definition available.

Name:	su_LineOfCreditFacilitiesAssignedForSpecificPurposes
Namespace Prefix:	su_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The amount of undrawn borrowing facilities for liquidity purposes that may be available for future operating activities and to settle capital commitments.

No definition available.

Name:	su_UnusedBorrowingFacilitiesForLiquidityPurposes
Namespace Prefix:	su_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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Namespace Prefix:
Data Type:	na
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Name:	ifrs-full_BorrowingsByNameAxis=su_FullyRevolvingCreditFacilitiesThatExpireIn2020Member
Namespace Prefix:
Data Type:	na
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Period Type:

Name:	ifrs-full_BorrowingsByNameAxis=su_FullyRevolvingCreditFacilitiesThatExpireIn20182019Member
Namespace Prefix:
Data Type:	na
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Period Type:

Name:	ifrs-full_BorrowingsByNameAxis=su_CreditFacilitiesThatCanBeTerminatedAtAnyTimeByLenderMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_BorrowingsByNameAxis=su_CreditFacilitiesSupportingOutstandingCommercialPaperMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_BorrowingsByNameAxis=su_CreditFacilitiesSupportingStandbyLettersOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	ifrs-full_BusinessCombinationsAxis=su_CanadianOilSandsLimitedMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	ifrs-full_BorrowingsByNameAxis=su_CreditFacilitiesForGeneralPurposesMember
Namespace Prefix:
Data Type:	na
Balance Type:
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