Property, Plant and Equipment Table (details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Property, plant and equipment	5,424,699	$ 4,239,100
Accumulated depreciation	1,040,328	855,845
Net property, plant and equipment	4,384,371	3,383,255
Western Gas Partners [Member] | Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	2,839	2,584
Western Gas Partners [Member] | Gathering Systems [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	4,790,974	3,673,008
Western Gas Partners [Member] | Gathering Systems [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Western Gas Partners [Member] | Gathering Systems [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	47 years
Western Gas Partners [Member] | Pipelines And Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	151,107	146,008
Western Gas Partners [Member] | Pipelines And Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	15 years
Western Gas Partners [Member] | Pipelines And Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	45 years
Western Gas Partners [Member] | Assets Under Construction [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	464,507	405,633
Western Gas Partners [Member] | Other [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	15,272	$ 11,867
Western Gas Partners [Member] | Other [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Western Gas Partners [Member] | Other [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	40 years