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Acquisitions (Details Textual) (USD $)			12 Months Ended		0 Months Ended								12 Months Ended			1 Months Ended	12 Months Ended
Acquisitions (Details Textual) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 Mid-America Midstream Gas Services, LLC [Member]	Aug. 01, 2013 Mid-America Midstream Gas Services, LLC [Member] acre mi	Sep. 02, 2013 Barcas Field Services, LLC [Member] Trucks Trailers	Dec. 31, 2013 Glass Mountain Pipeline Llc [Member]	Dec. 31, 2012 Glass Mountain Pipeline Llc [Member]	Dec. 31, 2013 Ngl Energy Partners Lp [Member]	Dec. 31, 2012 Ngl Energy Partners Lp [Member]	Nov. 01, 2011 Ngl Energy Partners Lp [Member]	Aug. 01, 2013 Rose Valley I plant [Member] Mid-America Midstream Gas Services, LLC [Member] MMcf	Aug. 01, 2013 Rose Valley II plant [Member] Mid-America Midstream Gas Services, LLC [Member] MMcf	Dec. 31, 2013 Gathering and processing agreement [Member] Mid-America Midstream Gas Services, LLC [Member]	Aug. 01, 2013 Gathering and processing agreement [Member] Mid-America Midstream Gas Services, LLC [Member]	Dec. 31, 2013 Partnership Interest [Member] Glass Mountain Pipeline Llc [Member]	Jun. 30, 2012 Common Units [Member] Ngl Energy Partners Lp [Member]	Dec. 31, 2013 Computer system not purchased [Member] Barcas Field Services, LLC [Member]	Nov. 01, 2011 Acquisitions [Member] Common Units [Member] Ngl Energy Partners Lp [Member]	Sep. 30, 2012 Additional interest acquired [Member] Partnership Interest [Member] Glass Mountain Pipeline Llc [Member]	Dec. 31, 2013 Senior Notes [Member]	Dec. 31, 2013 SemStream [Member]	Dec. 31, 2012 SemStream [Member]	Dec. 31, 2013 SemStream [Member] Limited Partner [Member] Ngl Energy Partners Lp [Member]	Sep. 30, 2013 SemStream [Member] Limited Partner [Member] Partnership Interest [Member] Ngl Energy Partners Lp [Member]	Dec. 31, 2013 SemStream [Member] General Partner [Member] Ngl Energy Partners Lp [Member]	Sep. 30, 2013 SemStream [Member] General Partner [Member] Ngl Energy Partners Lp [Member]	Jun. 30, 2012 SemStream [Member] General Partner [Member] Ngl Energy Partners Lp [Member]	Nov. 01, 2011 SemStream [Member] General Partner [Member] Acquisitions [Member] Ngl Energy Partners Lp [Member]	Aug. 06, 2013 SemStream [Member] General Partner [Member] Additional interest acquired [Member] Ngl Energy Partners Lp [Member]
Business Acquisition [Line Items]
Limited partner units owned																		8,932,031					9,133,409
Payments to acquire businesses			$ 313,487,000		$ 48,969,000
Transaction costs expensed			3,600,000
Length of gathering pipeline acquired				200
Processing capacity											200	200
Net acre dedication acquired				540,000
Contract tenor														20 years
Percentage of contract which is fee based													100.00%
Post-acquisition capital expenditures related to acquisition				125,000,000
Trucks purchased					114
Trailers purchased					120
Equity method investments	565,124,000	387,802,000				132,181,000	74,434,000	208,848,000	174,398,000	184,000,000											208,848,000	174,398,000
Number of common units received due to dilution																201,378
Equity method investment, ownership percentage															50.00%				25.00%					12.80%	11.78%	11.78%	6.42%	7.50%	5.36%
Senior notes	300,000,000	0
Debt instrument, interest rate stated percentage																				7.50%
Change in acquisition price																	$ 1,000,000