Cost method investment ownership percentage.

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- Definition

Number of Cities in which Entity Operates

+ References

No definition available.

+ Details

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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.

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- Definition

Number of Refined Products Systems

+ References

No definition available.

+ Details

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- 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=56956515&loc=d3e1392-128463

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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

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- Definition

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

+ References

No definition available.

+ Details

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- 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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- 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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- Definition

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

+ References

No definition available.

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Data Type:	xbrli:integerItemType
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- References

No definition available.

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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.

+ References

No definition available.

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Description of Business and Basis of Presentation (Details)	12 Months Ended
	Dec. 31, 2016 state city segment system	Dec. 27, 2016	Oct. 03, 2016	Aug. 09, 2016	May 31, 2016	Dec. 31, 2015	Jul. 01, 2015	May 31, 2015	Nov. 03, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of pipeline systems	7
Number of refined products systems	3
Number of natural gas gathering pipeline systems	1
Number of cities served \| city	70
Number of states served \| state	16
Schedule of Equity Method Investments [Line Items]
Number of segments \| segment	1
Zydeco
Schedule of Equity Method Investments [Line Items]
Minority interest ownership percentage by parent	92.50%
Minority interest ownership percentage by noncontrolling owners	7.50%				7.50%	37.50%		37.50%	57.00%
Pecten
Schedule of Equity Method Investments [Line Items]
Minority interest ownership percentage by parent	100.00%
Explorer
Schedule of Equity Method Investments [Line Items]
Voting interest acquired	2.62%			2.62%
Bengal
Schedule of Equity Method Investments [Line Items]
Equity method investment percentage	50.00%					49.00%
Odyssey
Schedule of Equity Method Investments [Line Items]
Equity method investment percentage	49.00%					0.00%
Odyssey \| Odyssey
Schedule of Equity Method Investments [Line Items]
Voting interest acquired			49.00%
Mars
Schedule of Equity Method Investments [Line Items]
Equity method investment percentage	48.60%					28.60%
Poseidon
Schedule of Equity Method Investments [Line Items]
Equity method investment percentage	36.00%					36.00%	36.00%
Proteus
Schedule of Equity Method Investments [Line Items]
Equity method investment percentage	10.00%					0.00%
Proteus \| December 2016 Acquisition
Schedule of Equity Method Investments [Line Items]
Voting interest acquired		10.00%
Endymion
Schedule of Equity Method Investments [Line Items]
Equity method investment percentage	10.00%					0.00%
Endymion \| December 2016 Acquisition
Schedule of Equity Method Investments [Line Items]
Voting interest acquired		10.00%
Colonial
Schedule of Equity Method Investments [Line Items]
Ownership	6.00%					3.00%
Cleopatra
Schedule of Equity Method Investments [Line Items]
Ownership	1.00%					0.00%
Cleopatra \| December 2016 Acquisition
Schedule of Equity Method Investments [Line Items]
Voting interest acquired		1.00%