Goodwill and Other Intangible Assets (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net, beginning balance	$ 174,838us-gaap_FiniteLivedIntangibleAssetsNet	$ 7,585us-gaap_FiniteLivedIntangibleAssetsNet	$ 8,950us-gaap_FiniteLivedIntangibleAssetsNet
Amortization	(15,875)us-gaap_AmortizationOfIntangibleAssets	(6,018)us-gaap_AmortizationOfIntangibleAssets	(2,017)us-gaap_AmortizationOfIntangibleAssets
Currency translation adjustments	(545)	9	652
Finite-Lived Intangible Assets, Net, ending balance	173,065us-gaap_FiniteLivedIntangibleAssetsNet	174,838us-gaap_FiniteLivedIntangibleAssetsNet	7,585us-gaap_FiniteLivedIntangibleAssetsNet
Crude [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net, ending balance	16,640	5,775
SemGas [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net, ending balance	152,383	163,144
Barcas Field Services, LLC [Member] \| Crude [Member]
Finite-Lived Intangible Assets [Line Items]
Customer contract intangible asset acquired		6,930
Indefinite-lived Intangible Assets, Purchase Accounting Adjustments	(50)
Mid-America Midstream Gas Services, LLC [Member] \| SemGas [Member]
Finite-Lived Intangible Assets [Line Items]
Customer contract intangible asset acquired		166,332
Indefinite-lived Intangible Assets, Purchase Accounting Adjustments	(2,313)
Chesapeake crude oil trucking assets [Member] \| Crude [Member]
Finite-Lived Intangible Assets [Line Items]
Customer contract intangible asset acquired	$ 17,010

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

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-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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

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