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

The decrease in equity resulting from the purchase of treasury shares. [Refer: Treasury shares]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 106
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_106_d&doctype=Standard
-URIDate 2021-03-24

Name:	ifrs-full_PurchaseOfTreasuryShares
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The amount of liabilities attributable to share repurchase commitment.

No definition available.

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

Represents the number of common shares purchased for cancellation.

No definition available.

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

The repurchase of average per share.

No definition available.