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Debt and Interest Expense - Debt Activity Table (Details) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended	6 Months Ended
	Mar. 14, 2016	Apr. 30, 2016	Mar. 31, 2016	Jun. 30, 2016
Debt Instrument [Line Items]
Beginning balance			$ 2,690,651	$ 2,690,651
Ending balance				2,960,004
Revolving Credit Facility [Member] \| WGP RCF [Member]
Debt Instrument [Line Items]
RCF Borrowings	$ 25,000		$ 28,000	28,000
Western Gas Partners, LP [Member]
Debt Instrument [Line Items]
Other				1,353
Western Gas Partners, LP [Member] \| Revolving Credit Facility [Member] \| WES RCF [Member]
Debt Instrument [Line Items]
RCF Borrowings				530,000
Repayments of RCF borrowings		$ (250,000)		$ (290,000)