Equity and Partners' Capital - Limited Partner and General Partner Units (details) (Western Gas Partners [Member])	1 Months Ended											12 Months Ended
	Jan. 31, 2014	Dec. 31, 2013		May 31, 2013		Jun. 30, 2012		Sep. 30, 2011		Mar. 31, 2011		Dec. 31, 2013	Dec. 31, 2012
Capital Unit [Line Items]
Balance												106,796,483	91,980,612
Long-term incentive plan awards												12,648	12,827
Common units issued		4,500,000	[1],[2]	7,015,000	[1]	5,000,000	[1]	5,750,000	[1]	3,852,813	[1]
Balance		119,717,157										119,717,157	106,796,483
Mountain Gas Resources [Member]
Capital Unit [Line Items]
Acquisition													645,697
June 2012 Equity Offering [Member]
Capital Unit [Line Items]
Offering													5,102,041
Chipeta Processing Limited Liability Company [Member]
Capital Unit [Line Items]
Acquisition													154,321
Western Gas Equity Partners [Member]
Capital Unit [Line Items]
WGP unit purchase agreement													8,900,985
Non-Operated Marcellus Interest [Member]
Capital Unit [Line Items]
Acquisition												458,295
May 2013 Equity Offering [Member]
Capital Unit [Line Items]
Offering												7,158,163
Continuous Offering Program [Member]
Capital Unit [Line Items]
Offering												699,731
December 2013 Equity Offering [Member]
Capital Unit [Line Items]
Offering												4,591,837
Common Units [Member]
Capital Unit [Line Items]
Balance												104,660,553	90,140,999
Long-term incentive plan awards												12,395	12,570
Balance		117,322,812										117,322,812	104,660,553
Common Units [Member] | Mountain Gas Resources [Member]
Capital Unit [Line Items]
Acquisition													632,783
Common Units [Member] | June 2012 Equity Offering [Member]
Capital Unit [Line Items]
Common units issued													5,000,000
Common Units [Member] | Chipeta Processing Limited Liability Company [Member]
Capital Unit [Line Items]
Acquisition													151,235
Common Units [Member] | Western Gas Equity Partners [Member]
Capital Unit [Line Items]
WGP unit purchase agreement													8,722,966
Common Units [Member] | Non-Operated Marcellus Interest [Member]
Capital Unit [Line Items]
Acquisition												449,129
Common Units [Member] | May 2013 Equity Offering [Member]
Capital Unit [Line Items]
Common units issued												7,015,000
Common Units [Member] | Continuous Offering Program [Member]
Capital Unit [Line Items]
Common units issued												685,735
Common Units [Member] | December 2013 Equity Offering [Member]
Capital Unit [Line Items]
Common units issued												4,500,000
General Partner [Member]
Capital Unit [Line Items]
Balance	2,394,345											2,135,930	1,839,613
Long-term incentive plan awards												253	257
Offering	6,122	91,837	[2],[3]	143,163	[3]	102,041	[3]	117,347	[3]	78,629	[3]
Balance		2,394,345										2,394,345	2,135,930
General Partner [Member] | Mountain Gas Resources [Member]
Capital Unit [Line Items]
Acquisition													12,914
General Partner [Member] | June 2012 Equity Offering [Member]
Capital Unit [Line Items]
Offering													102,041
General Partner [Member] | Chipeta Processing Limited Liability Company [Member]
Capital Unit [Line Items]
Acquisition													3,086
General Partner [Member] | Western Gas Equity Partners [Member]
Capital Unit [Line Items]
WGP unit purchase agreement													178,019
General Partner [Member] | Non-Operated Marcellus Interest [Member]
Capital Unit [Line Items]
Acquisition												9,166
General Partner [Member] | May 2013 Equity Offering [Member]
Capital Unit [Line Items]
Offering												143,163
General Partner [Member] | Continuous Offering Program [Member]
Capital Unit [Line Items]
Offering												13,996
General Partner [Member] | December 2013 Equity Offering [Member]
Capital Unit [Line Items]
Offering												91,837

[1] Includes the issuance of 302,813 WES common units, 750,000 WES common units and 915,000 WES common units pursuant to the full exercise of the underwriters’ over-allotment option granted in connection with the March 2011, September 2011 and May 2013 equity offerings, respectively.

[2] Excludes the issuance of 300,000 WES common units on January 3, 2014, pursuant to the partial exercise of the underwriters’ over-allotment option, and the corresponding issuance of 6,122 general partner units of WES to WES GP in exchange for WES GP’s proportionate capital contribution to maintain its 2.0% general partner interest. Total net proceeds for the partial exercise of the underwriters’ over-allotment option (including the WES GP’s proportionate capital contribution) were $18.3 million.

[3] Represents general partner units of WES issued to WES GP in exchange for WES GP’s proportionate capital contribution to maintain its 2.0% general partner interest.