Goodwill and Other Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2013 Crude [Member]	Dec. 31, 2012 Crude [Member]	Dec. 31, 2013 SemGas [Member]	Dec. 31, 2012 SemGas [Member]	Dec. 31, 2013 SemMexico [Member]	Dec. 31, 2012 SemMexico [Member]	Sep. 02, 2013 Barcas Field Services, LLC [Member] Crude [Member]	Aug. 01, 2013 Mid-America Midstream Gas Services, LLC [Member] SemGas [Member]
Goodwill [Line Items]
Goodwill	$ 62,021	$ 9,884	$ 9,453	$ 107,823	$ 28,322	$ 0	$ 23,839	$ 0	$ 9,860	$ 9,884	$ 28,322	$ 23,839

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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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