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

No definition available.

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- Definition

Tangible Equity Units Number Of Units Settled

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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 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

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

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- Details

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Noncontrolling Interests (Detail) - shares shares in Thousands			6 Months Ended	12 Months Ended
	Jun. 07, 2018	Mar. 01, 2017	Jun. 30, 2018	Dec. 31, 2017	Dec. 31, 2016
Western Gas Partners, LP [Member] \| Limited Partner [Member]
Noncontrolling Interest [Line Items]
Public ownership interest in subsidiary			59.50%
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			29.70%
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			9.30%
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] \| Limited Partner [Member]
Noncontrolling Interest [Line Items]
Ownership interest in subsidiary			77.80%
Public ownership interest in subsidiary			22.20%
Series A Preferred Units [Member] \| Western Gas Partners, LP [Member]
Noncontrolling Interest [Line Items]
Units issued in private placement					22,000
Percentage of units converted		50.00%
Class C Units [Member] \| Western Gas Partners, LP [Member]
Noncontrolling Interest [Line Items]
Units issued in private placement			534	886
Equity Component of 7.50% Tangible Equity Units [Member] \| Settled in WGP Common Units [Member]
Noncontrolling Interest [Line Items]
Number of tangible equity units settled	9,200
Shares, Issued	8,200