Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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-Section 45

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Expense related to distribution, servicing and underwriting fees.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-SubTopic 210

-Section S99

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

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Date the credit facility terminates, in CCYY-MM-DD format.

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The effective interest rate at the end of the reporting period.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Percent of offering price to public.

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Debt and Interest Expense - Additional Information (Details) - USD ($)	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Jun. 30, 2015	Nov. 01, 2012
Working Capital Facility [Member] \| Anadarko [Member]
Debt Instrument [Line Items]
Facility, interest rate at period end	1.69%	1.66%
Facility, outstanding borrowings	$ 0
Facility, available borrowing capacity	$ 30,000,000.0
Facility, maximum borrowing capacity				$ 30,000,000.0
Facility, expiration date	Nov. 01, 2017
Western Gas Partners, LP [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Facility, interest rate at period end	1.49%	1.46%
Facility, fee rate	0.20%	0.20%
Facility, outstanding borrowings	$ 180,000,000
Outstanding letters of credit	12,800,000
Facility, available borrowing capacity	$ 1,000,000,000
Facility, expiration date	Feb. 26, 2019
Western Gas Partners, LP [Member] \| Senior Notes [Member] \| 5.375% Senior Notes due 2021 [Member]
Debt Instrument [Line Items]
Fixed interest rate	5.375%
Debt instrument, maturity date	Jun. 01, 2021
Western Gas Partners, LP [Member] \| Senior Notes [Member] \| 4.000% Senior Notes due 2022 [Member]
Debt Instrument [Line Items]
Fixed interest rate	4.00%
Debt instrument, maturity date	Jul. 01, 2022
Western Gas Partners, LP [Member] \| Senior Notes [Member] \| 2.600% Senior Notes due 2018 [Member]
Debt Instrument [Line Items]
Fixed interest rate	2.60%
Debt instrument, maturity date	Aug. 15, 2018
Western Gas Partners, LP [Member] \| Senior Notes [Member] \| 5.450% Senior Notes due 2044 [Member]
Debt Instrument [Line Items]
Fixed interest rate	5.45%
Debt instrument, maturity date	Apr. 01, 2044
Western Gas Partners, LP [Member] \| Senior Notes [Member] \| 3.950% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Fixed interest rate	3.95%
Offering Percent			98.789%
Effective interest rate	4.205%
Underwriting discount	$ 3,300,000
Debt instrument, maturity date	Jun. 01, 2025