Description of Business and Basis of Presentation - Ownership Interest and Method of Consolidation Table (Details)			9 Months Ended
		Mar. 17, 2017	Sep. 30, 2017
Chipeta [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest by noncontrolling interest owner			25.00%
Western Gas Partners, LP [Member] | DBJV System [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership percentage acquired	[1]	50.00%
Western Gas Partners, LP [Member] | Equity Investments [Member] | Fort Union [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Percentage ownership interest	[2]		14.81%
Western Gas Partners, LP [Member] | Equity Investments [Member] | White Cliffs [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Percentage ownership interest	[2]		10.00%
Western Gas Partners, LP [Member] | Equity Investments [Member] | Rendezvous [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Percentage ownership interest	[2]		22.00%
Western Gas Partners, LP [Member] | Equity Investments [Member] | Mont Belvieu JV [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Percentage ownership interest	[2]		25.00%
Western Gas Partners, LP [Member] | Equity Investments [Member] | Texas Express Pipeline LLC [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Percentage ownership interest	[2]		20.00%
Western Gas Partners, LP [Member] | Equity Investments [Member] | Texas Express Gathering LLC [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Percentage ownership interest	[2]		20.00%
Western Gas Partners, LP [Member] | Equity Investments [Member] | Front Range Pipeline LLC [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Percentage ownership interest	[2]		33.33%
Western Gas Partners, LP [Member] | Proportionate Consolidation [Member] | Marcellus Interest Systems [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Percentage ownership interest	[3]		33.75%
Western Gas Partners, LP [Member] | Proportionate Consolidation [Member] | Newcastle System [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Percentage ownership interest	[3]		50.00%
Western Gas Partners, LP [Member] | Proportionate Consolidation [Member] | Springfield System [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Percentage ownership interest	[3]		50.10%
Western Gas Partners, LP [Member] | Full Consolidation [Member] | Chipeta [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Percentage ownership interest	[4]		75.00%
Western Gas Partners, LP [Member] | Full Consolidation [Member] | DBJV System [Member]
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Percentage ownership interest	[5]		100.00%

[1] WES acquired the Additional DBJV System Interest from a third party. See Property exchange below.

[2] Investments in non-controlled entities over which WES exercises significant influence are accounted for under the equity method. “Equity investment throughput” refers to WES’s share of average throughput for these investments.

[3] WGP proportionately consolidates WES’s associated share of the assets, liabilities, revenues and expenses attributable to these assets.

[4] The 25% interest in Chipeta Processing LLC (“Chipeta”) held by a third-party member is reflected within noncontrolling interests in the consolidated financial statements, in addition to the noncontrolling interests noted below.

[5] WES acquired an additional 50% interest in the DBJV system (the “Additional DBJV System Interest”) from a third party on March 17, 2017. See Note 2.