Administrative Fees, Inflationary Increase (Decrease), Percent

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Distribution Payable, Number Of Consecutive Quarters

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Distribution To Holders Of Incentive Distribution Rights Waived

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Distributions Payable, Amount Waved

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- Definition

Operations And Maintenance, Related Parties

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- Definition

Other Severance, Salaries And Other Payroll Expenses, Related Party

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- Definition

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

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cost for defined contribution plan.

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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- Definition

Amount of cost (reversal of cost) for other postretirement benefits. Excludes pension benefits.

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- Definition

Amount paid to managing member or general partner, affiliate of managing member or general partner, or affiliate of limited liability company (LLC) or limited partnership (LP) for administrative services provided to the LLC or LP, for example, but not limited to, salaries, rent, or overhead costs.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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Related Party Transactions - Additional Information (Details) $ in Millions			3 Months Ended				9 Months Ended			12 Months Ended
	Feb. 18, 2020	Nov. 03, 2014 USD ($)	Sep. 30, 2020 USD ($) credit_facility	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Sep. 30, 2020 USD ($) credit_facility	Sep. 30, 2019 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2019 USD ($)	Apr. 01, 2020 USD ($) numberOfQuarters
Related Party Transaction [Line Items]
Inflationary increase in general and administrative fee, percent	3.00%
Statute of limitations expirations, number of days		60 days
Distribution to holders of incentive distribution rights waived				$ 16	$ 17	$ 17				$ 50
Health and life insurance costs			$ 1	2			$ 4	$ 5
Defined contribution benefit plan costs			1	1			2	2
Severance Costs			1				6
Operations and maintenance – related parties			30	14			76	44	$ 44
Other			$ (2)	$ 0			$ 0	$ 0
Partnership Interests Restructuring Agreement \| General Partner SPLC
Related Party Transaction [Line Items]
Distributions payable, amount waved											$ 20
Distribution payable, number of consecutive quarters \| numberOfQuarters											4
Mattox Pipeline Company LLC \| Purchase And Sale Agreement
Related Party Transaction [Line Items]
Percentage of voting interests acquired											79.00%
Shell Treasury Center West Inc
Related Party Transaction [Line Items]
Number of revolving credit facilities \| credit_facility			5				5
Five Year Fixed Facility \| Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term							5 years
Five Year Fixed Facility \| Shell Treasury Center West Inc \| Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term							5 years
Five Year Revolver due December 2022 \| Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term							5 years
Five Year Revolver due December 2022 \| Shell Treasury Center West Inc \| Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term							5 years
Seven Year Fixed Facility \| Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term							7 years
Seven Year Fixed Facility \| Shell Treasury Center West Inc \| Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term							7 years
Ten Year Fixed Facility \| Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term							10 years
Ten Year Fixed Facility \| Shell Treasury Center West Inc \| Revolving Credit Facility
Related Party Transaction [Line Items]
Debt instrument term							10 years
Shell Pipeline Company L P
Related Party Transaction [Line Items]
Payment of general and administrative fee		$ 11
Odyssey Pipeline L.L.C. (“Odyssey”) \| GEL Offshore Pipeline LLC
Related Party Transaction [Line Items]
Noncontrolling interest			29.00%				29.00%			29.00%
Zydeco Pipeline Company LLC (“Zydeco”) \| Shell Pipeline Company L P
Related Party Transaction [Line Items]
Noncontrolling interest			7.50%				7.50%			7.50%