Acquisitions and Divestitures - Additional Information (Details) - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015		Mar. 02, 2015
Property, Plant and Equipment [Line Items]
Deferred purchase price obligation - Anadarko, present value	[1]	$ 16,425			$ 188,674	[2]
Western Gas Partners, LP [Member] | Hugoton System [Member] | Held-for-sale [Member]
Property, Plant and Equipment [Line Items]
Long-term assets related to assets held for sale		65,600
Long-term liabilities related to assets held for sale		8,400
Western Gas Partners, LP [Member] | Hugoton System [Member] | Held-for-sale [Member] | Level 2 Inputs [Member] | Market Approach Valuation Technique [Member] | Fair Value Measurements Nonrecurring [Member]
Property, Plant and Equipment [Line Items]
Loss on assets held for sale		6,200
Western Gas Partners, LP [Member] | Delaware Basin JV Gathering LLC [Member] | Deferred Purchase Price Obligation - Anadarko [Member]
Property, Plant and Equipment [Line Items]
Deferred purchase price obligation - Anadarko, future value		22,920	$ 41,666	$ 282,807	282,807		$ 282,807
Deferred purchase price obligation - Anadarko, present value		$ 16,425	$ 29,150	$ 193,211	$ 188,674		$ 174,276	[3]
Discount rate percentage		10.00%
Deferred purchase price obligation to Anadarko - future value change		$ 259,900

[1] See Note 2.

[2] Financial information has been recast to include the financial position and results attributable to the Springfield interest. See Note 1 and Note 2.

[3] WES acquired Delaware Basin JV Gathering LLC (“DBJV”) from Anadarko. DBJV owns a 50% interest in a gathering system and related facilities. The DBJV gathering system and related facilities (the “DBJV system”) are located in the Delaware Basin in Loving, Ward, Winkler and Reeves Counties, Texas. WES will make a cash payment on March 31, 2020, to Anadarko as consideration for the acquisition of DBJV. At the acquisition date, WES estimated the future payment would be $282.8 million, the net present value of which was $174.3 million. For further information, including revisions to the estimated future payment, see DBJV acquisition—deferred purchase price obligation - Anadarko below.