Acquisition Acquisition (Details 1) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Business Acquisition [Line Items]
Goodwill	$ 60,676	$ 9,884
Barcas Field Services, LLC [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	16,690
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	6,018
Goodwill	27,261
Total assets acquired	$ 49,969

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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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