Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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Fair value portion of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. 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 820
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
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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.

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The estimated or actual value of the asset at the end of its useful life or when it is no longer serviceable (cannot be used for its original purpose).

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Property, Plant and Equipment - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Impairments	$ 15,535	$ 515,458	$ 5,125
Western Gas Partners, LP [Member] \| Newcastle System [Member]
Property, Plant and Equipment [Line Items]
Impairments	6,100
Western Gas Partners, LP [Member] \| Newcastle System [Member] \| Fair Value Measurements Nonrecurring [Member] \| Level 3 Inputs [Member] \| Income Approach Valuation Technique [Member]
Property, Plant and Equipment [Line Items]
Estimated fair value	3,100
Western Gas Partners, LP [Member] \| Equipment [Member]
Property, Plant and Equipment [Line Items]
Impairments	$ 9,400	14,400
Western Gas Partners, LP [Member] \| Equipment [Member] \| Fair Value Measurements Nonrecurring [Member] \| Level 3 Inputs [Member] \| Income Approach Valuation Technique [Member]
Property, Plant and Equipment [Line Items]
Estimated salvage value			$ 2,400
Western Gas Partners, LP [Member] \| Red Desert Complex [Member]
Property, Plant and Equipment [Line Items]
Impairments		280,200
Western Gas Partners, LP [Member] \| Red Desert Complex [Member] \| Fair Value Measurements Nonrecurring [Member] \| Level 3 Inputs [Member] \| Income Approach Valuation Technique [Member]
Property, Plant and Equipment [Line Items]
Estimated salvage value		6,300
Western Gas Partners, LP [Member] \| Hilight System [Member]
Property, Plant and Equipment [Line Items]
Impairments		220,900
Western Gas Partners, LP [Member] \| Hilight System [Member] \| Fair Value Measurements Nonrecurring [Member] \| Level 3 Inputs [Member] \| Income Approach Valuation Technique [Member]
Property, Plant and Equipment [Line Items]
Estimated fair value		$ 28,800