Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013
Cash flows from operating activities
Net income	$ 293,705		$ 193,905	[1]
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and impairments	130,009		106,551	[1]
Non-cash equity-based compensation expense	3,333		2,783	[1]
Deferred income taxes	642		29,216	[1]
Debt-related amortization and other items, net	2,045		1,756	[1]
Equity income, net	(41,322)	[2],[3],[4]	(11,944)	[1],[2],[3],[4]
Distributions from equity investment earnings	43,061	[2]	15,563	[1],[2]
Changes in assets and liabilities:
(Increase) decrease in accounts receivable, net	(41,431)		(27,539)	[1]
Increase (decrease) in accounts and natural gas imbalance payables and accrued liabilities, net	8,895		6,700	[1]
Change in other items, net	2,281		(2,672)	[1]
Net cash provided by operating activities	401,218		314,319	[1]
Cash flows from investing activities
Capital expenditures	(492,287)		(469,678)	[1]
Investments in equity affiliates	(63,267)		(252,308)	[1]
Distributions from equity investments in excess of cumulative earnings	14,387	[2],[5]	0	[1],[2]
Net cash used in investing activities	(913,372)		(1,432,048)	[1]
Cash flows from financing activities
Borrowings, net of debt issuance costs	1,136,878		842,566	[1]
Repayments of debt	(480,000)		(495,000)	[1]
Increase (decrease) in outstanding checks	2,908		(3,335)	[1]
Offering expenses from the issuance of WGP common units	0		(2,367)	[1]
Distributions to WGP unitholders	(164,725)		(90,211)	[1]
Distributions to noncontrolling interest owners of WES	(129,247)		(94,117)	[1]
Net contributions from Anadarko	23,788		181,904	[1]
Net cash provided by financing activities	477,288		752,256	[1]
Net increase (decrease) in cash and cash equivalents	(34,866)		(365,473)	[1]
Cash and cash equivalents at beginning of period	113,085	[1]	422,556	[1]
Cash and cash equivalents at end of period	78,219		57,083	[1]
Supplemental disclosures
Net distributions to Anadarko of other assets	6,398		4,080	[1]
Interest paid, net of capitalized interest	43,504		34,974	[1]
Taxes paid (reimbursements received)	(340)		0	[1]
Capital lease asset transfer	4,833	[6]	0	[1],[6]
Western Gas Partners [Member]
Cash flows from financing activities
Proceeds from the issuance of WES common units, net of offering expenses	99,035		418,570	[1]
Chipeta Processing Limited Liability Company [Member]
Cash flows from financing activities
Contributions received from Chipeta noncontrolling interest owner	0		2,247	[1]
Distributions to Chipeta noncontrolling interest owner	(11,349)		(8,001)	[1]
Affiliated Entity [Member]
Cash flows from investing activities
Contributions in aid of construction costs from affiliates	183		0	[1]
Acquisitions	(372,393)		(469,884)	[1]
Proceeds from the sale of assets	0		82	[1]
Third Parties [Member]
Cash flows from investing activities
Acquisitions	0		(240,274)	[1]
Proceeds from the sale of assets	$ 5		$ 14	[1]

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

[2] Income earned on, distributions from and contributions to equity investments are classified as affiliate. See Note 1.

[3] Income earned from equity investments is classified as affiliate. See Note 1.

[4] 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.

[5] 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.

[6] For the nine months ended September 30, 2014, represents transfers of $0.2 million and $4.6 million from other current assets and other long-term assets, respectively, associated with the capital lease components of a processing agreement. See Note 6.