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Debt and Interest Expense - Debt Activity Table (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Changes in Debt Outstanding [Roll Forward]
Beginning balance	$ 7,901,304	$ 6,785,362
Commercial paper borrowings (repayments), net	(610,313)	609,916	$ 0
Ending balance	7,937,679	7,901,304	6,785,362
WES Operating [Member]
Changes in Debt Outstanding [Roll Forward]
Commercial paper borrowings (repayments), net	(610,313)	609,916	$ 0
Other	(1,494)	(8,829)
WES Operating [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	(150,000)	(276,700)
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member]
Changes in Debt Outstanding [Roll Forward]
RCF borrowings		1,120,000
Repayments of RCF borrowings		(1,495,000)
WES Operating [Member] \| Commercial Paper Program \| Commercial Paper Program
Changes in Debt Outstanding [Roll Forward]
Commercial paper borrowings (repayments), net	$ (610,312)	610,312
WES Operating [Member] \| 6.350% Senior Notes due 2029 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Proceeds from issuance senior notes		600,000
Senior note, interest rate	6.35%
WES Operating [Member] \| 6.150% Senior Notes due 2033 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Proceeds from issuance senior notes		750,000
Senior note, interest rate	6.15%
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)
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)	(50,000)
WES Operating [Member] \| 3.950% Senior Notes due 2025 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
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)	(7,038)
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)	(42,906)
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)	(17,112)
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)	(95,407)
Senior note, interest rate	4.05%
WES Operating [Member] \| Finance Lease Liability [Member]
Changes in Debt Outstanding [Roll Forward]
Finance lease liabilities	$ (1,819)	$ 29,285
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%