Equity Method Investments (Details Textual) $ / shares in Units, bbl in Thousands, $ in Thousands	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2015 USD ($) $ / shares shares	Sep. 30, 2014 USD ($)	Jun. 30, 2014	Sep. 30, 2015 USD ($) bbl $ / shares shares	Sep. 30, 2014 USD ($)	Jun. 30, 2015 shares
Schedule of Equity Method Investments [Line Items]
Gain on issuance of common units by equity method investee	$ 136	$ 18,772		$ 6,033	$ 26,899
General and administrative	23,045	23,296		78,272	63,882
Net proceeds from sale of common units of equity method investee				56,318	59,744
Gain on sale of common units of equity method investee				14,517	26,748
White Cliffs Pipeline, L.L.C. [Member]
Schedule of Equity Method Investments [Line Items]
General and administrative	400	400		1,100	1,200
NGL Energy Partners LP [Member]
Schedule of Equity Method Investments [Line Items]
Common units representing limited partner interests | shares						104,181,253
NGL Energy Partners LP [Member]
Schedule of Equity Method Investments [Line Items]
Gain on issuance of common units by equity method investee	$ 100	$ 18,800		$ 6,000	$ 26,900
Common units | shares	4,652,568			4,652,568
Closing price per common unit | $ / shares	$ 19.97			$ 19.97
Units of equity investee divested | shares				1,999,533
Net proceeds from sale of common units of equity method investee				$ 56,300
NGL Energy Partners LP [Member] | Limited Partner Interests [Member]
Schedule of Equity Method Investments [Line Items]
Limited partner ownership interest			4.50%
NGL Energy Partners LP [Member] | General Partner [Member]
Schedule of Equity Method Investments [Line Items]
General partner ownership interest					11.78%
White Cliffs Pipeline, L.L.C. [Member]
Schedule of Equity Method Investments [Line Items]
Project funding contributions				$ 31,000
Percentage of limited partner ownership interest	51.00%			51.00%
Glass Mountain Pipeline LLC [Member]
Schedule of Equity Method Investments [Line Items]
Project funding contributions				$ 2,000
Percentage of limited partner ownership interest	50.00%			50.00%
Pipeline expansion [Member] | White Cliffs Pipeline, L.L.C. [Member]
Schedule of Equity Method Investments [Line Items]
Project funding contributions				$ 22,700
Incremental capacity expected to be added | bbl				65
Expected capital contributions, year one				$ 14,000
Other Expense [Member] | NGL Energy Partners LP [Member]
Schedule of Equity Method Investments [Line Items]
Transaction related costs				500
Gain on sale of common units of equity method investee				14,500
Fair Value, Inputs, Level 1 [Member] | NGL Energy Partners LP [Member]
Schedule of Equity Method Investments [Line Items]
Fair market value of common units	$ 92,900			$ 92,900