Consolidated Statements of Cash Flows - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2017		Sep. 30, 2016
Cash flows from operating activities
Net income (loss)		$ 423,615		$ 452,711
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization		216,272		199,646
Impairments		170,079		11,313
Non-cash equity-based compensation expense		3,751		3,759
Deferred income taxes		3,882		2,321
Accretion and amortization of long-term obligations, net		3,701		(8,820)
Equity income, net – affiliates	[1]	(62,708)		(56,801)
Distributions from equity investment earnings – affiliates		64,313		59,671
(Gain) loss on divestiture and other, net		(135,017)		8,769
Lower of cost or market inventory adjustments		140		41
Changes in assets and liabilities:
(Increase) decrease in accounts receivable, net		(47,137)		(41,266)
Increase (decrease) in accounts and imbalance payables and accrued liabilities, net		4,127		24,227
Change in other items, net		(2,549)		(871)
Net cash provided by operating activities		642,469		654,700
Cash flows from investing activities
Capital expenditures		(419,193)		(372,725)
Investments in equity affiliates		(384)		139
Distributions from equity investments in excess of cumulative earnings – affiliates		16,255	[2]	16,592
Proceeds from property insurance claims		22,977		18,398
Net cash used in investing activities		(514,797)		(1,040,692)
Cash flows from financing activities
Borrowings, net of debt issuance costs		249,989		1,120,580
Repayments of debt		0		(880,000)
Increase (decrease) in outstanding checks		3,310		(1,070)
Distributions to WGP unitholders	[3]	(324,290)		(276,114)
Net contributions from (distributions to) Anadarko		30		(29,335)
Above-market component of swap agreements with Anadarko	[3]	46,719		34,782
Net cash provided by (used in) financing activities		(333,708)		432,646
Net increase (decrease) in cash and cash equivalents		(206,036)		46,654
Cash and cash equivalents at beginning of period		359,072		99,694
Cash and cash equivalents at end of period		153,036		146,348
Supplemental disclosures
Accretion expense and revisions to the Deferred purchase price obligation – Anadarko	[4]	(4,094)		(172,249)
Net distributions to (contributions from) Anadarko of other assets		(1,373)		581
Interest paid, net of capitalized interest		98,956		83,352
Taxes paid		189		67
Accrued capital expenditures		165,732		49,328
Fair value of properties and equipment from non-cash third party transactions	[4]	551,453		0
Chipeta [Member]
Cash flows from financing activities
Distributions to Chipeta noncontrolling interest owner		(9,049)		(11,257)
Western Gas Partners, LP [Member]
Cash flows from financing activities
Proceeds from the issuance of WES common units, net of offering expenses		(183)		0
Distributions to noncontrolling interest owners of WES		(262,888)		(211,877)
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		0		686,937
Affiliates [Member]
Cash flows from investing activities
Contributions in aid of construction costs from affiliates		1,386		4,927
Acquisitions		(3,910)		(716,465)
Proceeds from the sale of assets		0		623
Cash flows from financing activities
Settlement of the Deferred purchase price obligation - Anadarko	[4]	(37,346)		0
Distributions to WGP unitholders	[5]	(264,533)		(235,587)
Affiliates [Member] | Western Gas Partners, LP [Member]
Cash flows from financing activities
Distributions to WGP unitholders	[6]	(5,280)		(3,915)
Third Parties [Member]
Cash flows from investing activities
Acquisitions		(155,298)		0
Proceeds from the sale of assets		$ 23,370		$ 7,819

[1] Represents amounts earned or incurred on and subsequent to the date of the 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.

[2] 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.

[3] See Note 5.

[4] See Note 2.

[5] Represents distributions paid under WGP’s partnership agreement (see Note 3 and Note 4).

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