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
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-14

+ Details

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

- 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 S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

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

+ Details

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

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

- 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 S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-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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Namespace Prefix:	wes_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Changes in Debt Outstanding [Roll Forward]

+ References

No definition available.

+ Details

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Namespace Prefix:	wes_
Data Type:	xbrli:stringItemType
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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- Details

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Balance Type:
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- Details

Name:	us-gaap_DebtInstrumentAxis=wes_SeniorRevolvingCreditFacility1Member
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Balance Type:
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- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
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Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_DebtInstrumentAxis=wes_SeniorNotes6Point35PercentDue2029Member
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- Details

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- Details

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Debt and Interest Expense - Debt Activity Table (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Changes in Debt Outstanding [Roll Forward]
Beginning balance	$ 6,785,362
Ending balance	7,262,319
WES Operating [Member]
Changes in Debt Outstanding [Roll Forward]
Other	(10,332)
WES Operating [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	(276,700)
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member]
Changes in Debt Outstanding [Roll Forward]
RCF borrowings	470,000
Repayments of RCF borrowings	(845,000)
WES Operating [Member] \| 6.350% Senior Notes due 2029 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Proceeds from Issuance of Senior Long-Term Debt	600,000
WES Operating [Member] \| 6.150% Senior Notes due 2033 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Proceeds from Issuance of Senior Long-Term Debt	750,000
WES Operating [Member] \| Floating-Rate Senior Notes due 2023 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	(213,138)
WES Operating [Member] \| 3.100% Senior Notes due 2025 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	(64,225)	$ (1,400)
WES Operating [Member] \| 3.950% Senior Notes due 2025 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	(50,000)
WES Operating [Member] \| 4.650% Senior Notes due 2026 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	(7,038)
WES Operating [Member] \| 4.500% Senior Notes due 2028 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	(42,906)
WES Operating [Member] \| 4.750% Senior Notes due 2028 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	(17,112)
WES Operating [Member] \| 4.050% Senior Notes due 2030 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	(95,407)
WES Operating [Member] \| Finance Lease Liability [Member]
Changes in Debt Outstanding [Roll Forward]
Finance lease liabilities	$ 2,115