Business Acquisition, Barges Acquired

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- Definition

Business Acquisition, Tug Boats Acquired

+ References

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Number of Pipelines

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- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

+ References

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- Definition

Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 6

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-Name Accounting Standards Codification

-Glossary Acquisition Date

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-Subparagraph (b)

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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

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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

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- Definition

Monetary value of the issuance of new units of limited partnership interest in a public offering, net of offering costs. This is a parenthetical disclosure.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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- Definition

Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment).

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Acquisitions (Narrative) (Details) $ / shares in Units, $ in Thousands					1 Months Ended	12 Months Ended
	Nov. 13, 2014 USD ($)	Sep. 26, 2014 USD ($) $ / shares	Sep. 16, 2013 USD ($) $ / shares	Mar. 28, 2012 USD ($) $ / shares	Jan. 31, 2012	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Jul. 22, 2013 USD ($) Tug_Boats Barges	Jan. 03, 2012 Pipelines
Business Acquisition [Line Items]
Partners' Capital Account, Public Sale of Units Net of Offering Costs		$ 225,725	$ 263,574	$ 169,421
Price per share of common units issued \| $ / shares		$ 50.71	$ 47.51	$ 30.80
Proceeds from issuance of senior unsecured notes, including premium						$ 350,000	$ 350,000	$ 101,000
Cash paid for acquisition						$ 157,000	$ 230,880	$ 205,576
Property, Plant and Equipment, Estimated Useful Lives						25
American Phoenix Acquisition [Member]
Business Acquisition [Line Items]
Effective date of acquisition	Nov. 13, 2014
Transaction costs related to business acquisition	$ 157,000
Hornbeck Acquisition [Member]
Business Acquisition [Line Items]
Number of barges acquired \| Barges									9
Business Acquisition, Tug Boats Acquired \| Tug_Boats									9
Transaction costs related to business acquisition									$ 230,900
Gulf Of Mexico Crude Oil Pipeline Systems [Member]
Business Acquisition [Line Items]
Effective date of acquisition					Jan. 03, 2012
Poseidon Oil Pipeline Company, L.L.C. [Member]
Business Acquisition [Line Items]
Ownership percentage						28.00%
Marathon Offshore Pipeline, LLC [Member]
Business Acquisition [Line Items]
Ownership percentage						100.00%
Odyssey Pipeline L.L.C. [Member]
Business Acquisition [Line Items]
Ownership percentage						29.00%
Eugene Island Pipeline System [Member]
Business Acquisition [Line Items]
Ownership percentage						23.00%
Two Offshore Smaller Pipelines [Member]
Business Acquisition [Line Items]
Ownership percentage						100.00%
Number of piepelines \| Pipelines										2
CHOPS [Member]
Business Acquisition [Line Items]
Ownership percentage						50.00%