Consolidated Statements of Cash Flows - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2016		Sep. 30, 2015
Cash flows from operating activities
Net income (loss)		$ 452,711		$ 165,855	[1]
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization		199,646		204,896	[1]
Impairments		11,313		276,579	[1]
Non-cash equity-based compensation expense		3,759		3,453	[1]
Deferred income taxes		2,321		9,996	[1]
Accretion and amortization of long-term obligations, net		(8,820)		12,296	[1]
Equity income, net – affiliates	[2]	(56,801)		(59,137)	[1]
Distributions from equity investment earnings – affiliates		59,671		60,645	[1]
(Gain) loss on divestiture and other, net		8,769		(77,248)	[1]
Lower of cost or market inventory adjustments		41		0	[1]
Changes in assets and liabilities:
(Increase) decrease in accounts receivable, net		(41,266)		(18,778)	[1]
Increase (decrease) in accounts and imbalance payables and accrued liabilities, net		24,227		17,792	[1]
Change in other items, net		(871)		(1,053)	[1]
Net cash provided by operating activities		654,700		595,296	[1]
Cash flows from investing activities
Capital expenditures		(372,725)		(505,848)	[1]
Investments in equity affiliates		139		(9,052)	[1]
Distributions from equity investments in excess of cumulative earnings – affiliates		16,592	[3]	12,409	[1]
Proceeds from property insurance claims		18,398		0	[1]
Net cash used in investing activities		(1,040,692)		(368,651)	[1]
Cash flows from financing activities
Borrowings, net of debt issuance costs		1,120,580		769,606	[1]
Repayments of debt		(880,000)		(611,150)	[1]
Increase (decrease) in outstanding checks		(1,070)		(2,435)	[1]
Distributions to WGP unitholders	[4]	(276,114)		(223,016)	[1]
Net contributions from (distributions to) Anadarko		(29,335)		(35,403)	[1]
Above-market component of swap extensions with Anadarko	[4]	34,782		7,916	[1]
Net cash provided by (used in) financing activities		432,646		(219,016)	[1]
Net increase (decrease) in cash and cash equivalents		46,654		7,629	[1]
Cash and cash equivalents at beginning of period		99,694	[5]	67,213	[1]
Cash and cash equivalents at end of period		146,348		74,842	[1]
Supplemental disclosures
Net distributions to (contributions from) Anadarko of other assets		581		4,250	[1]
Interest paid, net of capitalized interest		83,352		60,612	[1]
Taxes paid (reimbursements received)		67		(138)	[1]
Delaware Basin JV Gathering LLC [Member]
Supplemental disclosures
Acquisition of DBJV from Anadarko		(172,249)		174,276	[1]
Chipeta Processing Limited Liability Company [Member]
Cash flows from financing activities
Distributions to Chipeta noncontrolling interest owner		(11,257)		(10,150)	[1]
Western Gas Partners, LP [Member]
Cash flows from financing activities
Proceeds from the issuance of common units, net of offering expenses		0		57,353	[1]
Distributions to noncontrolling interest owners of WES		(211,877)		(171,737)	[1]
Western Gas Partners, LP [Member] | Series A Preferred Units [Member]
Cash flows from financing activities
Proceeds from the issuance of WES Series A Preferred units, net of offering expenses		686,937		0	[1]
Affiliates [Member]
Cash flows from investing activities
Contributions in aid of construction costs from affiliates		4,927		0	[1]
Acquisitions		(716,465)		(10,369)	[1]
Proceeds from the sale of assets		623		700	[1]
Affiliates [Member] | Western Gas Partners, LP [Member]
Cash flows from financing activities
Distributions to WGP unitholders	[6]	(3,915)		(1,648)
Third Parties [Member]
Cash flows from investing activities
Acquisitions		0		(3,514)	[1]
Proceeds from the sale of assets		$ 7,819		$ 147,023	[1]

[1] Financial information has been recast to include the financial position and results attributable to the Springfield interest. See Note 1 and Note 2.

[2] Represents amounts earned or incurred on and subsequent to the date of acquisition of WES assets, as well as amounts earned or incurred by Anadarko on a historical basis related to WES assets prior to the acquisition of such assets by WES, recognized under gathering, treating or processing agreements, and purchase and sale agreements.

[3] Distributions in excess of cumulative earnings, classified as investing cash flows in the consolidated statements of cash flows, is calculated on an individual investment basis.

[4] See Note 5.

[5] Financial information has been recast to include the financial position and results attributable to the Springfield interest. See Note 1 and Note 2.

[6] Represents distributions paid to other subsidiaries of Anadarko under WES’s partnership agreement (see Note 3 and Note 4).