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Goodwill and Other Intangible Assets (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 48,032	$ 58,326	$ 62,021
Currency translation adjustments	(750)	(806)	(702)
Goodwill, Ending Balance	34,230	48,032	58,326
SemGas [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	13,052
Goodwill, Impairment Loss	(13,052)
Goodwill, Ending Balance	0	13,052
Crude Transportation [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	26,628
Goodwill, Impairment Loss		(9,488)
Goodwill, Ending Balance	$ 26,628	$ 26,628
Barcas Field Services, LLC [Member]
Goodwill [Line Items]
Goodwill, Purchase Accounting Adjustments			(98)
Mid-America Midstream Gas Services, LLC [Member]
Goodwill [Line Items]
Goodwill, Purchase Accounting Adjustments			(10,787)
Chesapeake crude oil trucking assets [Member]
Goodwill [Line Items]
Goodwill, Acquired During Period			$ 7,892