Amount of cost for defined contribution plan.

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The value of gas balancing asset or liability as of the end of the period.

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Carrying value as of the balance sheet date of obligations incurred and payable to an underproduced working interest owner when an overproduced working interest owner has sold gas in excess of the party's ownership percentage. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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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 number of limited partner units outstanding.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The cash inflow from an entity that is affiliated with the entity by means of direct or indirect ownership.

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Summary of Significant Accounting Policies and Basis of Presentation - Additional Information (Details) - USD ($)		3 Months Ended	12 Months Ended
	Dec. 31, 2019	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Feb. 28, 2019
Common units outstanding			402,993,919	413,839,863
Imbalance receivables			$ 25,309,000	$ 12,976,000
Imbalance payables			16,600,000	3,300,000
Goodwill impairment			0	441,017,000	$ 0
Goodwill			4,783,000	4,783,000
Defined-contribution plan expense			$ 23,700,000	12,500,000
Gathering and Processing Reporting Unit [Member]
Goodwill				$ 0
WES Operating [Member]
Ownership interest by noncontrolling interest owner			2.00%
Chipeta [Member]
Ownership interest by noncontrolling interest owner			25.00%
WES [Member] \| WES Operating [Member]
Ownership interest			98.00%
Occidental [Member] \| WES [Member]
Ownership interest			48.60%
General partner's interest	2.00%		2.20%
Common units outstanding			200,281,578
Occidental [Member] \| WES [Member] \| Common Units [Member]
Common units outstanding	9,060,641				9,060,641
Occidental [Member] \| WES Operating [Member]
Ownership interest			2.00%
WES Operating [Member]
Common units outstanding			318,675,578	318,675,578
Cash contribution from related party		$ 20,000,000
Imbalance receivables			$ 25,309,000	$ 12,976,000
Goodwill impairment			0	441,017,000	$ 0
Goodwill			4,783,000	$ 4,783,000
WES Operating [Member] \| Revolving Credit Facility [Member] \| RCF [Member]
Facility, maximum borrowing capacity			$ 2,000,000,000			$ 2,000,000,000