Debt and Interest Expense - Debt Activity Table (Details) $ in Thousands	9 Months Ended
Sep. 30, 2017 USD ($)
Debt Instrument [Line Items]
Beginning balance	$ 3,119,461
Other	2,425
Ending balance	3,371,886
Western Gas Partners, LP [Member] \| Revolving Credit Facility [Member] \| WES RCF [Member]
Debt Instrument [Line Items]
RCF borrowings	$ 250,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Represents debt issuance costs, including but not limited to legal, accounting, underwriting, printing and registration costs for debt issuances during the year, in addition to amortization of expense attributable to debt discount (premium) and debt issuance costs.

+ References

No definition available.

+ Details

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- Details

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