Equity and Partners' Capital - Limited Partner and General Partner Units Table (Details) - Western Gas Partners, LP [Member] - shares		1 Months Ended	9 Months Ended
		Nov. 30, 2014	Sep. 30, 2015
Capital Unit [Line Items]
Balance			141,192,051
PIK Class C units			316,961
Long-Term Incentive Plan award vestings			5,991
Balance			142,388,528
500 Million COP [Member]
Capital Unit [Line Items]
Offering			873,525
Common Units [Member]
Capital Unit [Line Items]
Balance			127,695,130
Long-Term Incentive Plan award vestings			5,991
Offering	[1]	8,620,153
Balance			128,574,646
Common Units [Member] | 500 Million COP [Member]
Capital Unit [Line Items]
Offering	[2]		873,525
Class C Units [Member]
Capital Unit [Line Items]
Balance			10,913,853
PIK Class C units			316,961
Balance			11,230,814
General Partner [Member]
Capital Unit [Line Items]
Balance			2,583,068
PIK Class C units	[1],[3]	153,061
Balance			2,583,068

[1] Includes the issuance of 1,120,153 WES common units pursuant to the partial exercise of the underwriters’ over-allotment option, the net proceeds from which were $77.0 million. Beginning with this partial exercise, WES GP elected not to make a corresponding capital contribution to maintain its 2.0% interest in WES.

[2] Represents common units of WES issued during the nine months ended September 30, 2015, pursuant to WES’s registration statement filed with the SEC in August 2014 authorizing the issuance of up to an aggregate of $500.0 million of WES common units (the “$500.0 million COP”). Gross proceeds generated during the three and nine months ended September 30, 2015, were zero and $58.2 million, respectively. Commissions paid during the three and nine months ended September 30, 2015, were zero and $0.6 million, respectively. The price per unit in the table above represents an average price for all issuances under the $500.0 million COP during the nine months ended September 30, 2015.

[3] Represents general partner units of WES issued to WES GP in exchange for WES GP’s proportionate capital contribution.