Transactions with Affiliates - Commodity Price Swap Agreements Extensions Tables (Details) - Western Gas Partners, LP [Member]		Dec. 08, 2015 $ / MMBTU $ / bbl	Jun. 25, 2015 $ / MMBTU $ / bbl
Year 2015 [Member] | DJ Basin Complex [Member] | Ethane [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price			18.41
Commodity market price	[1]		1.96
Year 2015 [Member] | DJ Basin Complex [Member] | Propane [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price			47.08
Commodity market price	[1]		13.10
Year 2015 [Member] | DJ Basin Complex [Member] | Isobutane [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price			62.09
Commodity market price	[1]		19.75
Year 2015 [Member] | DJ Basin Complex [Member] | Normal butane [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price			54.62
Commodity market price	[1]		18.99
Year 2015 [Member] | DJ Basin Complex [Member] | Natural gasoline [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price			72.88
Commodity market price	[1]		52.59
Year 2015 [Member] | DJ Basin Complex [Member] | Condensate [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price			76.47
Commodity market price	[1]		52.59
Year 2015 [Member] | DJ Basin Complex [Member] | Natural gas (per MMBtu) [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price | $ / MMBTU			5.96
Commodity market price | $ / MMBTU	[1]		2.75
Year 2015 [Member] | Hugoton System [Member] | Condensate [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price			78.61
Commodity market price	[1]		32.56
Year 2015 [Member] | Hugoton System [Member] | Natural gas (per MMBtu) [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price | $ / MMBTU			5.50
Commodity market price | $ / MMBTU	[1]		2.74
Year 2016 [Member] | DJ Basin Complex [Member] | Ethane [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price		18.41
Commodity market price	[2]	0.60
Year 2016 [Member] | DJ Basin Complex [Member] | Propane [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price		47.08
Commodity market price	[2]	10.98
Year 2016 [Member] | DJ Basin Complex [Member] | Isobutane [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price		62.09
Commodity market price	[2]	17.23
Year 2016 [Member] | DJ Basin Complex [Member] | Normal butane [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price		54.62
Commodity market price	[2]	16.86
Year 2016 [Member] | DJ Basin Complex [Member] | Natural gasoline [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price		72.88
Commodity market price	[2]	26.15
Year 2016 [Member] | DJ Basin Complex [Member] | Condensate [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price		76.47
Commodity market price	[2]	34.65
Year 2016 [Member] | DJ Basin Complex [Member] | Natural gas (per MMBtu) [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price | $ / MMBTU		5.96
Commodity market price | $ / MMBTU	[2]	2.11
Year 2016 [Member] | Hugoton System [Member] | Condensate [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price		78.61
Commodity market price	[2]	18.81
Year 2016 [Member] | Hugoton System [Member] | Natural gas (per MMBtu) [Member]
Commodity Price Risk Swap [Line Items]
Commodity swap fixed price | $ / MMBTU		5.50
Commodity market price | $ / MMBTU	[2]	2.12

[1] Represents the New York Mercantile Exchange (“NYMEX”) forward strip price as of June 25, 2015, adjusted for product specification, location, basis and, in the case of NGLs, transportation and fractionation costs.

[2] Represents the NYMEX forward strip price as of December 8, 2015, adjusted for product specification, location, basis and, in the case of NGLs, transportation and fractionation costs.