Organization consolidation and presentation of financial statements.

No definition available.

Name:	sun_OrganizationConsolidationAndPresentationOfFinancialStatementsLineItems
Namespace Prefix:	sun_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

+ Details

Name:	us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

Name:	us-gaap_LimitedLiabilityCompanyLLCOrLimitedPartnershipLPManagingMemberOrGeneralPartnerOwnershipInterest
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfOperatingSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfStatesInWhichEntityOperates
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_BusinessAcquisitionAxis=sun_SunocoLimitedLiabilityCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=sun_SunocoRetailLimitedLiabilityCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ProductOrServiceAxis=sun_MotorFuelsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ProductOrServiceAxis=sun_ConvenienceandRetailStoresMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Organization and Principles of Consolidation - Additional Information (Details)		3 Months Ended
	Apr. 01, 2015	Mar. 31, 2017 state segment	Sep. 30, 2016 state	Jan. 01, 2016
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Percentage of membership interest acquired		100.00%
Number of operating segments \| segment		2
Sunoco LLC [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Ownership Percentage	50.10%
Percentage of membership interest acquired	31.58%
Sunoco LLC [Member] \| Minimum [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of states in which entity operates (more than)		26
Sunoco Retail LLC [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Ownership Percentage				100.00%
Motor Fuels [Member] \| Minimum [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of states in which entity operates (more than)			30
Convenience and Retail Stores [Member] \| Minimum [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of states in which entity operates (more than)			20