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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.

+ References

No definition available.

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 272
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- Definition

The amount of ownership interest of different classes of partners in limited partnership.

+ References

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- Definition

The number of each class of partnership units outstanding at the balance sheet date. Units represent shares of ownership of the general, limited, and preferred partners.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

The number of units sold in a private placement of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

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(Deficit) Equity (Details) - USD ($)	3 Months Ended	9 Months Ended
(Deficit) Equity (Details) - USD ($)	Jun. 30, 2020	Sep. 30, 2020	Apr. 01, 2020	Dec. 31, 2019
Class of Stock [Line Items]
Partners' capital		$ (437,000,000)		$ (775,000,000)
Issuance of common units, maximum proceeds		$ 300,000,000
General Partner SPLC
Class of Stock [Line Items]
Capital units, publicly owned (in shares)		0		4,761,012
Partners' capital			$ (4,000,000,000)
Common Units
Class of Stock [Line Items]
Units issued under the ATM Program (in shares)		1,000,000,000
Shell Pipeline Company L P \| General Partner SPLC \| General Partner Interest
Class of Stock [Line Items]
Aggregate percentage of general partner interest	2.00%
Shell Pipeline Company L P \| Limited Partner \| Limited Partner Interest
Class of Stock [Line Items]
Aggregate percentage of general partner interest	98.00%
Shell Pipeline Company L P \| Common Units
Class of Stock [Line Items]
Capital units, publicly owned (in shares)		269,457,304		109,457,304