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Debt and Interest Expense - Debt Activity Table (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Changes in Debt Outstanding [Roll Forward]
Beginning balance	$ 7,901,304
Commercial paper borrowings (repayments), net	(610,312)	$ 0
Ending balance	7,937,230		$ 7,901,304
WES Operating [Member]
Changes in Debt Outstanding [Roll Forward]
Commercial paper borrowings (repayments), net	(610,312)	$ 0
Other	(3,511)
WES Operating [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	(150,000)		$ (276,700)
WES Operating [Member] \| Commercial Paper Program \| Commercial Paper Program
Changes in Debt Outstanding [Roll Forward]
Commercial paper borrowings (repayments), net	(610,312)
WES Operating [Member] \| 5.450% Senior Notes due 2034 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Proceeds from issuance senior notes	$ 800,000
Senior note, interest rate	5.45%
WES Operating [Member] \| 3.100% Senior Notes due 2025 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	$ (2,650)
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	$ (12,405)
Senior note, interest rate	3.95%
WES Operating [Member] \| 4.650% Senior Notes due 2026 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	$ (26,699)
Senior note, interest rate	4.65%
WES Operating [Member] \| 4.500% Senior Notes due 2028 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	$ (14,159)
Senior note, interest rate	4.50%
WES Operating [Member] \| 4.750% Senior Notes due 2028 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	$ (46,628)
Senior note, interest rate	4.75%
WES Operating [Member] \| 4.050% Senior Notes due 2030 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	$ (47,459)
Senior note, interest rate	4.05%
WES Operating [Member] \| Finance Lease Liability [Member]
Changes in Debt Outstanding [Roll Forward]
Finance lease liabilities	$ (251)