Debt and Interest Expense - Debt Activity Table (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Beginning balance	$ 2,424,104	$ 1,418,169
Ending balance	2,707,357	2,424,104
Working Capital Facility [Member] \| Anadarko [Member]
Debt Instrument [Line Items]
Borrowings		1,150
Repayments	(1,150)
Western Gas Partners, LP [Member]
Debt Instrument [Line Items]
Other	(5,597)	(5,215)
Western Gas Partners, LP [Member] \| Senior Notes [Member] \| 5.450% Senior Notes due 2044 [Member]
Debt Instrument [Line Items]
Issuance of Senior Notes		400,000
Western Gas Partners, LP [Member] \| Senior Notes [Member] \| 2.600% Senior Notes due 2018 [Member]
Debt Instrument [Line Items]
Issuance of Senior Notes		100,000
Western Gas Partners, LP [Member] \| Senior Notes [Member] \| 3.950% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Issuance of Senior Notes	500,000
Western Gas Partners, LP [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Borrowings	400,000	1,160,000
Repayments	$ (610,000)	$ (650,000)

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

Reference 1: 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=56944662&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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