Description of Business and Basis of Presentation - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
NGLs inventory	$ 837		$ 2,733
Materials and supplied inventory - short term	13,965		10,103
Materials and supplies inventory - long term	$ 141,900		131,600
Long-Term Incentive Plans [Member]
Equity-based compensation, number of units issued	941,869	770,505
Equity-based compensation, expense	$ 11,000	$ 8,200
Natural-Gas Liquids [Member]
NGLs line-fill inventory	$ 4,500		$ 3,200
WES Operating [Member]
Ownership interest by noncontrolling interest owner	1.90%	2.00%	1.90%
Chipeta [Member]
Ownership interest by noncontrolling interest owner	25.00%
WES [Member] \| WES Operating [Member]
Ownership interest	98.10%
Occidental [Member] \| WES Operating [Member]
Ownership interest	1.90%

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Carrying amount as of the balance sheet date of liquid hydrocarbon components recovered from natural gas.

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Inventories not expected to be converted to cash, sold or exchanged within the normal operating cycle.

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Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

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The carrying amount of capitalized costs of materials, supplies, and other assets, which are not included in inventory but used in production.

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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed, classified as non-current.

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