Debt - Debt Activity Table (Details) $ in Thousands	3 Months Ended
Mar. 31, 2025 USD ($)
Changes in Debt Outstanding [Roll Forward]
Beginning balance	$ 7,937,679
Ending balance	7,275,630
WES Operating [Member]
Changes in Debt Outstanding [Roll Forward]
Other	1,872
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] \| Finance Lease Liability [Member]
Changes in Debt Outstanding [Roll Forward]
Finance lease liabilities	$ (90)

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

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Changes in Debt Outstanding [Roll Forward]

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- 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.

+ Details

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Namespace Prefix:	wes_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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- Details

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