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The amount of identifiable intangible assets recognized as of the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Acquisitions (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Sep. 02, 2013
Business Acquisition [Line Items]
Goodwill acquired	$ 58,326us-gaap_Goodwill	$ 62,021us-gaap_Goodwill	$ 9,884us-gaap_Goodwill	$ 9,453us-gaap_Goodwill
Crude [Member]
Business Acquisition [Line Items]
Goodwill acquired	36,116	28,322
Crude [Member] \| Barcas Field Services, LLC [Member]
Business Acquisition [Line Items]
Property, plant, and equipment acquired					13,865
Customer contract intangible asset acquired					6,880
Goodwill acquired					28,234
Total assets acquired					$ 48,979