Partnership Distributions - Cash Distributions Table (details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Sep. 30, 2014		Jun. 30, 2014	Mar. 31, 2014	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013
Dividends Payable [Line Items]
Total quarterly distribution per unit	$ 0.29125	[1]	$ 0.27125	$ 0.25000	$ 0.21375	$ 0.19750	$ 0.17875
Total quarterly cash distribution	$ 63,756	[1]	$ 59,378	$ 54,726	$ 46,789	$ 43,232	$ 39,128
Western Gas Partners [Member]
Dividends Payable [Line Items]
Total quarterly distribution per unit	$ 0.675	[2]	$ 0.650	$ 0.625	$ 0.580	$ 0.560	$ 0.540
Total quarterly cash distribution	$ 111,609	[2]	$ 105,655	$ 98,749	$ 83,986	$ 79,315	$ 70,143

[1] On October 20, 2014, the board of directors of WGP GP declared a cash distribution to WGP unitholders of $0.29125 per unit, or $63.8 million in aggregate. The cash distribution is payable on November 21, 2014, to WGP unitholders of record at the close of business on October 31, 2014.

[2] On October 20, 2014, the board of directors of WES GP declared a cash distribution to WES unitholders of $0.675 per unit, or $111.6 million in aggregate, including incentive distributions. The cash distribution is payable on November 13, 2014, to WES unitholders of record at the close of business on October 31, 2014.