Acquisitions - Pro Forma Condensed Financial Information Table (details) (Anadarko-Operated Marcellus Interest [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012
Anadarko-Operated Marcellus Interest [Member]
Business Acquisition [Line Items]
Revenues	$ 764,128	$ 682,820
Net income	194,074	124,221
Net income attributable to Western Gas Equity Partners, LP	$ 111,512	$ 52,963
Net income per common unit - basic and diluted	$ 0.49

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

+ Details

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

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The pro forma net Income or Loss, including portion attributable to noncontrolling interest for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

No definition available.

+ Details

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