Debt and Interest Expense - Debt Activity Table (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Changes in Debt Outstanding [Roll Forward]
Beginning balance	$ 7,854,702	$ 7,959,438
Other	9,509	(30,747)
Ending balance	6,906,548	7,854,702
WES Operating [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	(500,000)	(218,000)
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member]
Changes in Debt Outstanding [Roll Forward]
Facility borrowings	480,000	220,000
Repayments of facility borrowings	(480,000)	(600,000)
WES Operating [Member] \| Floating-Rate Senior Notes due 2023 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Issuance of senior notes		300,000
Repayments of senior notes	(26,840)	(60,022)
WES Operating [Member] \| 3.100% Senior Notes due 2025 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Issuance of senior notes		1,000,000
Repayments of senior notes	$ (267,894)
Senior note, interest rate	3.10%
WES Operating [Member] \| 4.050% Senior Notes due 2030 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Issuance of senior notes		1,200,000
Senior note, interest rate	4.05%
WES Operating [Member] \| 5.250% Senior Notes due 2050 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Issuance of senior notes		1,000,000
Senior note, interest rate	5.25%
WES Operating [Member] \| Finance Lease Liability [Member]
Changes in Debt Outstanding [Roll Forward]
Finance lease liabilities	$ (26,582)	24,035
WES Operating [Member] \| Term Loan Facility [Member] \| Revolving Credit Facility [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of facility borrowings		(3,000,000)
WES Operating [Member] \| 5.375% Senior Notes due 2021 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	$ (431,081)	(68,919)
Senior note, interest rate	5.375%
WES Operating [Member] \| 4.000% Senior Notes due 2022 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	$ (78,671)	$ (89,083)
Senior note, interest rate	4.00%
WES Operating [Member] \| 3.950% Senior Notes due 2025 [Member] \| Senior Notes [Member]
Changes in Debt Outstanding [Roll Forward]
Repayments of senior notes	$ (100,837)
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	$ (25,758)
Senior note, interest rate	4.65%

Contractual interest rate for funds borrowed, under the debt agreement.

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