Noncontrolling Interests - Subsequent Events (Details) (USD $) In Millions, except Share data, unless otherwise specified	6 Months Ended		0 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014 Western Gas Equity Partners, LP [Member] Limited Partner [Member]	Jul. 07, 2014 Subsequent Event [Member] Western Gas Equity Partners, LP [Member] Limited Partner [Member]	Jul. 07, 2014 Subsequent Event [Member] Western Gas Equity Partners, LP [Member] Limited Partner [Member]
Noncontrolling Interest [Line Items]
Common units issued to the public				5,750,000
Net proceeds raised from offering	$ 92	$ 415		$ 335
Ownership interest in subsidiary			91.00%		88.30%

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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- Definition

The number of units sold in a public offering of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 5

-Subparagraph (SAB TOPIC 4.F)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 16

-Subparagraph a, b

-Article 6

+ Details

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- Definition

The cash inflow from the issuance of common limited partners units during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

+ Details

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