The number of general partner units outstanding.

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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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Amount, before allowance for credit loss, of financing receivable.

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The number of units redeemed during the year of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

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The number of units sold in a public offering of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

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The cash outflow to reacquire common stock during the period.

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased and retired during the period.

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The number of units sold as part of the over-allotment option of a public offering.

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The percentage interest in the Anadarko Note Receivable transferred to an affiliate as part of a financial transaction.

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Equity and Partners' Capital - Additional Information (Details) - USD ($)		1 Months Ended	9 Months Ended
	Sep. 11, 2020	Mar. 31, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Nov. 30, 2020	May 31, 2008
Schedule of Investments [Line Items]
Common units outstanding			408,610,916		413,839,863
General partner units outstanding			9,060,641		9,060,641
Unit repurchases, authorized amount						$ 250,000,000
Unit repurchases, number of units			5,586,419
Unit repurchases, amount			$ 104,366,000	$ 0
Unit repurchases, remaining authorized amount			$ 113,100,000
Related Parties [Member]
Schedule of Investments [Line Items]
Anadarko note receivable							$ 260,000,000
Anadarko [Member]
Schedule of Investments [Line Items]
Anadarko note receivable - percentage interest transferred	98.00%
Anadarko note receivable	$ 260,000,000
WES [Member] \| Public [Member]
Schedule of Investments [Line Items]
Common units outstanding			205,829,338
Limited partner's interest			49.30%
WES [Member] \| WES [Member] \| Related Parties [Member] \| Limited Partner [Member]
Schedule of Investments [Line Items]
Units redeemed from a related party	27,855,398
WES [Member] \| WES Operating [Member]
Schedule of Investments [Line Items]
Limited partner's interest			98.00%
Occidental [Member] \| Limited Partner [Member]
Schedule of Investments [Line Items]
Units sold by a related party		11,500,000
Units sold by a related party, over-allotment		1,500,000
Occidental [Member] \| WES [Member]
Schedule of Investments [Line Items]
Common units outstanding			202,781,578
Limited partner's interest			48.50%
General partner units outstanding			9,060,641
General partner's interest			2.20%
Occidental [Member] \| WES Operating [Member]
Schedule of Investments [Line Items]
Limited partner's interest			2.00%
WES Operating [Member]
Schedule of Investments [Line Items]
Common units outstanding			318,675,578		318,675,578