Debt - Debt Activity Table (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2025	Dec. 31, 2024
Changes in Debt Outstanding [Roll Forward]
Beginning balance	$ 7,937,679
Ending balance	6,937,353	$ 7,937,679
WES Operating [Member]
Changes in Debt Outstanding [Roll Forward]
Other	5,146
WES Operating [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes		$ (150,000)
WES Operating [Member] \| 3.100% Senior Notes due 2025 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	$ (663,831)
Senior note, interest rate	3.10%
WES Operating [Member] \| 3.950% Senior Notes due 2025 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	$ (336,758)
Senior note, interest rate	3.95%
WES Operating [Member] \| Finance Lease Liability [Member]
Changes in Debt Outstanding [Roll Forward]
Finance lease liabilities	$ (4,883)

Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(a)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

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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 outflow for short-term and long-term debt. Excludes payment of lease obligation.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 15
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-15

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- Definition

Net increases (decreases) of finance lease liabilities recorded as debt on the balance sheet.

+ References

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- Definition

Changes in Debt Outstanding [Roll Forward]

+ References

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- Definition

Increase (decrease) representing debt issuance costs, including but not limited to legal, accounting, underwriting, printing and registration costs for debt issuance 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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