Percentage of convertible preferred unit that will be converted to common units on a designated date.

No definition available.

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- Definition

Number of tangible equity units issued during the period.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

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

+ References

No definition available.

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- Definition

The number of units sold in a private placement 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 FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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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 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-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

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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
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

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- Definition

The cash inflow associated with the amount received from entity's raising of capital via private rather than public placement.

+ References

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Noncontrolling Interests (Detail) - USD ($) shares in Thousands, $ in Millions		12 Months Ended
	Mar. 01, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
7.50% Tangible Equity Units [Member]
Noncontrolling Interest [Line Items]
Number of tangible equity units issued				9,200
Western Gas Partners, LP [Member]
Noncontrolling Interest [Line Items]
Units issued in private placement			1,300
Units issued to the public				874
Net proceeds raised from public offering				$ 57
Western Gas Partners, LP [Member] \| Limited Partner [Member]
Noncontrolling Interest [Line Items]
Public ownership interest in subsidiary		59.60%
Western Gas Partners, LP [Member] \| Limited Partner [Member] \| Western Gas Equity Partners, LP Ownership Interest in Western Gas Partners, LP [Member]
Noncontrolling Interest [Line Items]
Ownership interest in subsidiary		29.80%
Western Gas Partners, LP [Member] \| Limited Partner [Member] \| Anadarko Limited Partner Interest In WES Owned Through Other Subsidiaries [Member]
Noncontrolling Interest [Line Items]
Ownership interest in subsidiary		9.10%
Western Gas Partners, LP [Member] \| General Partner [Member] \| Western Gas Equity Partners, LP Ownership Interest in Western Gas Partners, LP [Member]
Noncontrolling Interest [Line Items]
Ownership interest in subsidiary		1.50%
Western Gas Equity Partners LP [Member]
Noncontrolling Interest [Line Items]
Units issued to the public			12,500	2,300
Net proceeds raised from public offering			$ 476	$ 130
Western Gas Equity Partners LP [Member] \| Limited Partner [Member]
Noncontrolling Interest [Line Items]
Ownership interest in subsidiary		81.60%
Public ownership interest in subsidiary		18.40%
Convertible Preferred Units [Member] \| Western Gas Partners, LP [Member]
Noncontrolling Interest [Line Items]
Units issued in private placement			22,000
Percentage of preferred units converted	50.00%
Proceeds from issuance of private placement			$ 687
Class C Units [Member] \| Western Gas Partners, LP [Member]
Noncontrolling Interest [Line Items]
Units issued in private placement		886	946	498