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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Debt and Interest Expense - Debt Activity Table (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Changes in Debt Outstanding [Roll Forward]
Beginning balance	$ 7,901,304
Commercial paper borrowings (repayments), net	(510,379)	$ 0
Ending balance	7,380,473		$ 7,901,304
WES Operating [Member]
Changes in Debt Outstanding [Roll Forward]
Commercial paper borrowings (repayments), net	(510,379)	$ 0
Other	1,905
WES Operating [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	(15,100)		$ (276,700)
WES Operating [Member] \| Commercial Paper Program \| Commercial Paper Program
Changes in Debt Outstanding [Roll Forward]
Commercial paper borrowings (repayments), net	(510,379)
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	$ (518)
Senior note, interest rate	3.95%
WES Operating [Member] \| 4.500% Senior Notes due 2028 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	$ (6,919)
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	$ (1,040)
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	$ (3,981)
Senior note, interest rate	4.05%
WES Operating [Member] \| Finance Lease Liability [Member]
Changes in Debt Outstanding [Roll Forward]
Finance lease liabilities	$ 2,751