Debt - Debt Outstanding Table (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
Total short-term debt, principal	$ 13,233	$ 1,011,545
Total short-term debt, carrying value	13,233	1,011,032
Total long-term debt, carrying value	6,924,108	6,926,647
Valuation, Market Approach [Member] \| Level-2 Inputs [Member]
Debt Instrument [Line Items]
Short-term debt, fair value	13,233	1,008,622
Long-Term Debt Obligations [Member]
Debt Instrument [Line Items]
Total long-term debt, principal	6,994,558	7,000,163
Total long-term debt, carrying value	6,924,108	6,926,647
Long-Term Debt Obligations [Member] \| Valuation, Market Approach [Member] \| Level-2 Inputs [Member]
Debt Instrument [Line Items]
Long-term debt, fair value	6,600,950	6,571,456
WES Operating [Member]
Debt Instrument [Line Items]
Total short-term debt, carrying value	13,233	1,011,032
Total long-term debt, carrying value	6,924,108	6,926,647
WES Operating [Member] \| Finance Lease Liability, Short Term [Member]
Debt Instrument [Line Items]
Finance leases - short-term debt	13,233	10,956
WES Operating [Member] \| Finance Lease Liability, Long Term [Member]
Debt Instrument [Line Items]
Finance leases - long-term debt	17,724	23,329
WES Operating [Member] \| Valuation, Market Approach [Member] \| Level-2 Inputs [Member] \| Finance Lease Liability, Short Term [Member]
Debt Instrument [Line Items]
Finance leases - short-term debt	13,233	10,956
WES Operating [Member] \| Valuation, Market Approach [Member] \| Level-2 Inputs [Member] \| Finance Lease Liability, Long Term [Member]
Debt Instrument [Line Items]
Finance leases - long-term debt	17,724	23,329
WES Operating [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Principal	6,976,834	6,976,834
Long-term debt, carrying value	6,906,384	6,903,318
WES Operating [Member] \| Senior Notes [Member] \| Valuation, Market Approach [Member] \| Level-2 Inputs [Member]
Debt Instrument [Line Items]
Long-term debt, fair value	6,583,226	6,548,127
WES Operating [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Principal	0	1,000,589
Short-term debt, carrying value	0	1,000,076
WES Operating [Member] \| Senior Notes [Member] \| Valuation, Market Approach [Member] \| Level-2 Inputs [Member]
Debt Instrument [Line Items]
Short-term debt, fair value	$ 0	$ 997,666

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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