Cost method investment ownership percentage.

No definition available.

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- Definition

Description of business and basis of presentation.

+ References

No definition available.

+ Details

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- Definition

Number Of Crude Tank Storage and Terminal Systems

+ References

No definition available.

+ Details

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- Definition

Number of Cities in which Entity Operates

+ References

No definition available.

+ Details

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Namespace Prefix:	shlx_
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Balance Type:	na
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- Definition

Number of Natural Gas Gathering Pipeline Systems

+ References

No definition available.

+ Details

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- Definition

Number of Pipeline Systems

+ References

No definition available.

+ Details

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- Definition

Number of Refined Products Systems

+ References

No definition available.

+ Details

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

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Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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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

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
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Period Type:	instant

- Details

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Description of Business and Basis of Presentation (Details)	3 Months Ended
	Mar. 31, 2017 state city segment system	Dec. 31, 2016	Mar. 31, 2016
Description Of Business And Basis Of Presentation [Line Items]
Number of pipeline systems	7
Number of refined products systems	3
Number of natural gas gathering pipeline systems	1
Number of crude tank storage and terminal systems	1
Number of cities the entity serves \| city	70
Number of states the entity serves \| state	16
Number of reportable segments \| segment	1
Pecten
Description Of Business And Basis Of Presentation [Line Items]
Ownership	100.00%
Zydeco
Description Of Business And Basis Of Presentation [Line Items]
Minority interest ownership percentage by parent	92.50%
Zydeco \| SPLC
Description Of Business And Basis Of Presentation [Line Items]
Noncontrolling Interest	7.50%	7.50%	37.50%
Bengal
Description Of Business And Basis Of Presentation [Line Items]
Ownership	50.00%	50.00%
Odyssey
Description Of Business And Basis Of Presentation [Line Items]
Ownership	49.00%	49.00%
Mars
Description Of Business And Basis Of Presentation [Line Items]
Ownership	48.60%	48.60%
Poseidon
Description Of Business And Basis Of Presentation [Line Items]
Ownership	36.00%	36.00%
Proteus
Description Of Business And Basis Of Presentation [Line Items]
Ownership	10.00%	10.00%
Endymion
Description Of Business And Basis Of Presentation [Line Items]
Ownership	10.00%	10.00%
Colonial
Description Of Business And Basis Of Presentation [Line Items]
Cost method investment percentage	6.00%
Explorer
Description Of Business And Basis Of Presentation [Line Items]
Cost method investment percentage	2.62%
Cleopatra
Description Of Business And Basis Of Presentation [Line Items]
Cost method investment percentage	1.00%