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Debt and Interest Expense - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Feb. 28, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Gain (loss) on early extinguishment of debt	$ (24,944,000)	$ 11,234,000	$ 0
Finance leases - Net property, plant, and equipment	5,449,000	31,487,000
Cash paid to settle interest-rate swaps	0	25,621,000	107,685,000
Accrued liability on interest-rate swaps	263,249,000	269,947,000
Gain (loss) on interest-rate swaps	0	0	125,334,000
WES Operating [Member]
Debt Instrument [Line Items]
Gain (loss) on early extinguishment of debt	(24,944,000)	11,234,000	0
Cash paid to settle interest-rate swaps	0	25,621,000	107,685,000
Accrued liability on interest-rate swaps	210,693,000	230,833,000
Gain (loss) on interest-rate swaps	0	0	125,334,000
WES Operating [Member] \| Interest-Rate Swaps [Member]
Debt Instrument [Line Items]
Cash paid to settle interest-rate swaps		25,600,000	107,700,000
Gain (loss) on interest-rate swaps			125,300,000
WES Operating [Member] \| Interest-Rate Swaps [Member] \| Not Designated as Hedging Instrument [Member]
Debt Instrument [Line Items]
Interest-rate swap, notional amount			1,125,000,000	$ 375,000,000		$ 750,000,000
Accrued liability on interest-rate swaps			$ 25,600,000
WES Operating [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Repayments of Debt	500,000,000	218,000,000
Gain (loss) on early extinguishment of debt	$ (24,900,000)	$ 13,500,000
WES Operating [Member] \| 3.100% Senior Notes due 2025 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Senior note, interest rate	3.10%
Senior note, effective interest rate	4.542%	4.291%
Repayments of Debt	$ 267,894,000
WES Operating [Member] \| 4.050% Senior Notes due 2030 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Senior note, interest rate	4.05%
Senior note, effective interest rate	5.424%	5.173%
WES Operating [Member] \| 5.250% Senior Notes due 2050 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Senior note, interest rate	5.25%
Senior note, effective interest rate	6.629%	6.375%
WES Operating [Member] \| Floating-Rate Senior Notes due 2023 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Senior note, effective interest rate	1.97%	2.07%
Repayments of Debt	$ 26,840,000	$ 60,022,000
WES Operating [Member] \| 5.375% Senior Notes due 2021 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Senior note, interest rate	5.375%
Repayments of Debt	$ 431,081,000	68,919,000
WES Operating [Member] \| 4.000% Senior Notes due 2022 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Senior note, interest rate	4.00%
Repayments of Debt	$ 78,671,000	89,083,000
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Facility, repayment of borrowings	480,000,000	$ 600,000,000
Facility, maximum borrowing capacity	2,000,000,000				$ 2,000,000,000
Facility, expandable maximum borrowing capacity	2,500,000,000
Facility, outstanding borrowings	0
Facility, outstanding letters of credit	5,100,000
Facility, available borrowing capacity	$ 2,000,000,000
Facility, interest rate at period end	1.60%	1.64%
Facility, fee rate	0.25%	0.25%
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member] \| Alternate Base Rate [Member]
Debt Instrument [Line Items]
Facility, applicable margin added	1.00%
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member] \| Percentage Above Federal Funds Effective Rate [Member] \| Alternate Base Rate [Member]
Debt Instrument [Line Items]
Facility, applicable margin added	0.50%
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Facility, applicable margin added	0.125%
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member] \| Minimum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Facility, applicable margin added	0.00%
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member] \| Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Facility, applicable margin added	1.00%
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Facility, applicable margin added	0.25%
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member] \| Maximum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Facility, applicable margin added	0.50%
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member] \| Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Facility, applicable margin added	1.50%
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member] \| Non-Extending Lender [Member]
Debt Instrument [Line Items]
Facility, borrowing capacity for non-extending lender	$ 100,000,000
WES Operating [Member] \| Term Loan Facility [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Gain (loss) on early extinguishment of debt		$ (2,300,000)
Facility, repayment of borrowings		$ 3,000,000,000