Administrative Fees, Inflationary Increase (Decrease), Percent

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- Definition

Distribution Payable, Number Of Consecutive Quarters

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- Definition

Distribution To Holders Of Incentive Distribution Rights Waived

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- Definition

Distributions Payable, Amount Waved

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- Definition

Number of revolving credit facilities.

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- Definition

Number of Days Within Combined Tax Filing Submission

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- Definition

Statute of Limitations Expirations, Number of Days

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

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

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No definition available.

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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			12 Months Ended
	Feb. 18, 2020	Nov. 03, 2014 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($) credit_facility	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Apr. 01, 2020 USD ($) numberOfQuarters
Related Party Transaction [Line Items]
Inflationary increase in general and administrative fee, percent	3.00%
Number of days within combined tax filing submission						15 days
Distribution to holders of incentive distribution rights waived			$ 16	$ 17	$ 17	$ 50
Health and life insurance costs						5	$ 6	$ 6
Defined contribution benefit costs						2	$ 2	3
Severance Costs						$ 7		$ 3
Five Year Revolver due July 2023
Related Party Transaction [Line Items]
Debt instrument term						5 years
Five Year Revolver Due December 2022
Related Party Transaction [Line Items]
Debt instrument term						5 years
Revolving Credit Facility \| Ten Year Fixed Facility
Related Party Transaction [Line Items]
Debt instrument term						10 years
Revolving Credit Facility \| Seven Year Fixed Facility
Related Party Transaction [Line Items]
Debt instrument term						7 years
Revolving Credit Facility \| Five Year Revolver due July 2023
Related Party Transaction [Line Items]
Debt instrument term						5 years
Revolving Credit Facility \| Five Year Fixed Facility
Related Party Transaction [Line Items]
Debt instrument term						5 years
Shell Treasury Center West Inc
Related Party Transaction [Line Items]
Number of revolving credit facilities \| credit_facility						5
Shell Treasury Center West Inc \| Revolving Credit Facility \| Ten Year Fixed Facility
Related Party Transaction [Line Items]
Debt instrument term						10 years
Shell Treasury Center West Inc \| Revolving Credit Facility \| Seven Year Fixed Facility
Related Party Transaction [Line Items]
Debt instrument term						7 years
Shell Treasury Center West Inc \| Revolving Credit Facility \| Five Year Revolver due July 2023
Related Party Transaction [Line Items]
Debt instrument term						5 years
Shell Treasury Center West Inc \| Revolving Credit Facility \| Five Year Revolver Due December 2022
Related Party Transaction [Line Items]
Debt instrument term						5 years
Shell Treasury Center West Inc \| Revolving Credit Facility \| Five Year Fixed Facility
Related Party Transaction [Line Items]
Debt instrument term						5 years
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
Zydeco Pipeline Company LLC (“Zydeco”) \| Shell Pipeline Company L P
Related Party Transaction [Line Items]
Noncontrolling interest						7.50%	7.50%	7.50%
Odyssey Pipeline L.L.C. (“Odyssey”) \| GEL Offshore Pipeline LLC
Related Party Transaction [Line Items]
Noncontrolling interest						29.00%	29.00%	29.00%
Omnibus Agreement
Related Party Transaction [Line Items]
Statute of limitations expirations, number of days						60 days
Omnibus Agreement \| Shell Pipeline Company L P
Related Party Transaction [Line Items]
Payment of general and administrative fee		$ 11