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Acquisitions (Details Textual) a in Thousands, $ in Thousands	Jun. 25, 2014 USD ($)	Sep. 02, 2013 USD ($) Trucks Trailers	Aug. 01, 2013 USD ($) a mi MMcf	Dec. 31, 2015 USD ($)	Jun. 23, 2014 Trucks Trailers	Aug. 06, 2013
Business Acquisition [Line Items]
Senior notes				$ 300,000
Senior Notes [Member]
Business Acquisition [Line Items]
Debt instrument, interest rate stated percentage				7.50%
Crude Transportation [Member] \| Chesapeake crude oil trucking assets [Member]
Business Acquisition [Line Items]
Payments to acquire businesses	$ 44,000
Trucks purchased \| Trucks					124
Trailers purchased \| Trailers					122
Crude Transportation [Member] \| Barcas Field Services, LLC [Member]
Business Acquisition [Line Items]
Payments to acquire businesses		$ 48,969
Trucks purchased \| Trucks		114
Trailers purchased \| Trailers		120
SemGas [Member] \| Mid-America Midstream Gas Services, LLC [Member]
Business Acquisition [Line Items]
Payments to acquire businesses			$ 314,001
Transaction costs expensed			$ 3,600
Length of gathering pipeline acquired \| mi			200
Net acre dedication acquired \| a			540
SemGas [Member] \| Rose Valley I plant [Member] \| Mid-America Midstream Gas Services, LLC [Member]
Business Acquisition [Line Items]
Processing capacity \| MMcf			200
SemGas [Member] \| Rose Valley II plant [Member] \| Mid-America Midstream Gas Services, LLC [Member]
Business Acquisition [Line Items]
Processing capacity \| MMcf			200
SemGas [Member] \| Gathering and processing agreement [Member] \| Mid-America Midstream Gas Services, LLC [Member]
Business Acquisition [Line Items]
Contract tenor			20 years
Percentage of contract which is fee based			100.00%
SemStream [Member] \| General Partner [Member] \| Ngl Energy Partners Lp [Member]
Business Acquisition [Line Items]
Equity method investment, ownership percentage				11.78%
SemStream [Member] \| General Partner [Member] \| Additional interest acquired [Member] \| Ngl Energy Partners Lp [Member]
Business Acquisition [Line Items]
Equity method investment, ownership percentage						5.36%