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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The number of units or percentage investment held in the subsidiary by the limited liability company or limited partnership.

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Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended
	Mar. 17, 2017	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Loss Contingencies [Line Items]
Contract liabilities		$ 22,024		$ 0
Western Gas Partners, LP [Member]
Loss Contingencies [Line Items]
Rent expense associated with office and equipment leases		13,800	$ 8,600
Western Gas Partners, LP [Member] \| DBJV Arbitration [Member] \| Pending Litigation [Member]
Loss Contingencies [Line Items]
Gathering fees sought In arbitration		194,200
Fees sought In counterclaim		$ 14,900
Percentage recovery from a third party		50.00%
Percentage due to third party		50.00%
Contract liabilities		$ 7,500
Western Gas Partners, LP [Member] \| Delaware Basin JV Gathering LLC [Member] \| DBJV Arbitration [Member]
Loss Contingencies [Line Items]
Percentage ownership interest	50.00%
Percentage third-party ownership interest	50.00%