Debt - Debt Activity Table (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Changes in Debt Outstanding [Roll Forward]
Beginning balance	$ 8,643,995
Commercial paper borrowings (repayments), net	162,905	$ 0
Ending balance	9,053,081
WES Operating [Member]
Changes in Debt Outstanding [Roll Forward]
Commercial paper borrowings (repayments), net	162,905	$ 0
Other	(7,534)
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member]
Changes in Debt Outstanding [Roll Forward]
RCF borrowings	360,000
RCF repayment	(360,000)
WES Operating [Member] \| Commercial Paper Program \| Commercial Paper Program
Changes in Debt Outstanding [Roll Forward]
Commercial paper borrowings (repayments), net	162,905
WES Operating [Member] \| 4.650% Senior Notes due 2026 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	(440,505)
WES Operating [Member] \| 5.700% Senior Notes due 2036 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Proceeds from issuance senior notes	700,000
WES Operating [Member] \| Finance Lease Liability [Member]
Changes in Debt Outstanding [Roll Forward]
Finance lease liabilities	$ (5,780)

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

No definition available.

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- Definition

The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
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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/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 230
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-Section 45
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-14

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- Definition

The net cash inflow or cash outflow from issuing (borrowing) and repaying commercial paper.

+ 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

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-14

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 9
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-9

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- Definition

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

+ References

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- Definition

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

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-Section 45
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-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

No definition available.

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- Definition

Changes in Debt Outstanding [Roll Forward]

+ References

No definition available.

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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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