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Debt and Interest Expense - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Jun. 30, 2021
Debt Instrument [Line Items]
Gain (loss) on early extinguishment of debt	$ 0	$ (24,655,000)	$ 91,000	$ (24,944,000)
WES Operating [Member]
Debt Instrument [Line Items]
Gain (loss) on early extinguishment of debt	0	$ (24,655,000)	91,000	$ (24,944,000)
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Facility, maximum borrowing capacity	2,000,000,000		2,000,000,000
Facility, expandable maximum borrowing capacity	2,500,000,000		2,500,000,000
Facility, outstanding borrowings	625,000,000		625,000,000
Facility, outstanding letters of credit	5,100,000		5,100,000
Facility, available borrowing capacity	$ 1,400,000,000		$ 1,400,000,000
Facility, interest rate at period end	4.65%	1.58%	4.65%	1.58%
Facility, fee rate			0.25%	0.25%
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member] \| Extending Lenders [Member]
Debt Instrument [Line Items]
Facility, borrowing capacity for extending and non-extending lender	$ 1,600,000,000		$ 1,600,000,000
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member] \| Non-Extending Lenders [Member]
Debt Instrument [Line Items]
Facility, borrowing capacity for extending and non-extending lender	$ 400,000,000		$ 400,000,000
WES Operating [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Repayments of senior notes		$ 500,000,000
Gain (loss) on early extinguishment of debt		$ (24,700,000)
WES Operating [Member] \| Senior Notes [Member] \| 3.100% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Senior note, interest rate	3.10%		3.10%
Senior note, effective interest rate	3.79%	4.542%	3.79%	4.542%
Repayments of senior notes			$ 1,400,000
WES Operating [Member] \| Senior Notes [Member] \| 4.050% Senior Notes due 2030 [Member]
Debt Instrument [Line Items]
Senior note, interest rate	4.05%		4.05%
Senior note, effective interest rate	4.671%	5.424%	4.671%	5.424%
WES Operating [Member] \| Senior Notes [Member] \| 5.250% Senior Notes due 2050 [Member]
Debt Instrument [Line Items]
Senior note, interest rate	5.25%		5.25%
Senior note, effective interest rate	5.869%	6.629%	5.869%	6.629%
WES Operating [Member] \| Senior Notes [Member] \| Floating-Rate Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Senior note, effective interest rate	3.56%	2.23%	3.56%	2.23%
WES Operating [Member] \| Senior Notes [Member] \| 4.000% Senior Notes due 2022 [Member]
Debt Instrument [Line Items]
Senior note, interest rate	4.00%		4.00%
Repayments of senior notes			$ 502,246,000
WES Operating [Member] \| Senior Notes [Member] \| 5.375% Senior Notes due 2021 [Member]
Debt Instrument [Line Items]
Senior note, interest rate					5.375%