Debt and Interest Expense - Debt Activity Table (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Changes in Debt Outstanding [Roll Forward]
Beginning balance	$ 3,492,712	$ 3,119,461
Other	(27,331)	3,251
Ending balance	4,815,381	3,492,712
Western Gas Partners, LP [Member] \| WES RCF [Member] \| Revolving Credit Facility [Member]
Changes in Debt Outstanding [Roll Forward]
RCF borrowings	540,000	$ 370,000
Repayments of RCF borrowings	(690,000)
Western Gas Partners, LP [Member] \| Senior Notes [Member] \| 4.500% Senior Notes due 2028 [Member]
Changes in Debt Outstanding [Roll Forward]
Issuance of senior notes	400,000
Western Gas Partners, LP [Member] \| Senior Notes [Member] \| 5.300% Senior Notes due 2048 [Member]
Changes in Debt Outstanding [Roll Forward]
Issuance of senior notes	700,000
Western Gas Partners, LP [Member] \| Senior Notes [Member] \| 4.750% Senior Notes due 2028 [Member]
Changes in Debt Outstanding [Roll Forward]
Issuance of senior notes	400,000
Western Gas Partners, LP [Member] \| Senior Notes [Member] \| 5.500% Senior Notes due 2048 [Member]
Changes in Debt Outstanding [Roll Forward]
Issuance of senior notes	350,000
Western Gas Partners, LP [Member] \| Senior Notes [Member] \| 2.600% Senior Notes due 2018 [Member]
Changes in Debt Outstanding [Roll Forward]
Repayment of senior notes	$ (350,000)

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

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

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-Section 45
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Changes in Debt Outstanding [Roll Forward]

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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.

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