Transactions with Affiliates - Equipment Purchases and Sales Table (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Related Party Transaction [Line Items]
Partners’ capital adjustment	$ (1,373)	$ 581
Western Gas Partners, LP [Member] \| Affiliates [Member] \| Purchases [Member]
Related Party Transaction [Line Items]
Cash consideration - purchases	3,910	3,965
Net carrying value	(5,283)	(3,366)
Partners’ capital adjustment	(1,373)	599
Western Gas Partners, LP [Member] \| Affiliates [Member] \| Sales [Member]
Related Party Transaction [Line Items]
Cash consideration - sales	0	623
Net carrying value	0	(605)
Partners’ capital adjustment	$ 0	$ (18)

The cash outflow to purchase long lived physical asset for use in the normal oil and gas operations and to purchase mineral interests in oil and gas properties not intended for resale.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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- Definition

The cash inflow from sale of machinery and equipment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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- Definition

Amount of increase (decrease) of physical assets used in the normal conduct of business and not intended for resale, from reclassification, impairment, donation, or changes classified as other. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84176398&loc=d3e2921-110230

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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

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- Definition

Total change in each class of partners' capital accounts during the year due to distributions to or contributions from affiliates of other assets.

+ References

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