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Purchase price of expected business acquisition prior to consideration being transferred. Excludes asset acquisition.

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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Face (par) amount of debt instrument at time of issuance.

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Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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The cash inflow associated with the deconsolidation of a previously consolidated subsidiary or the sale of investment in consolidated subsidiaries (generally greater than 50 percent).

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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The number of units or percentage investment held in the subsidiary by the limited liability company or limited partnership.

No definition available.

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

The pro forma adjustment to depreciation and amortization for a period as if the business combination or combinations had been completed at the beginning of the period.

No definition available.

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The pro forma adjustment to interest expense for a period as if the business combination or combinations had been completed at the beginning of the period.

No definition available.

Name:	wes_BusinessAcquisitionsAdjustmentToProFormaInterestExpense
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The pro forma adjustment to revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

No definition available.

Name:	wes_BusinessAcquisitionsAdjustmentToProFormaRevenue
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This element represents the amount of operating expense of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

No definition available.

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The gains and losses included in earnings resulting from the sale, disposal, or write-down of tangible assets; minerals revenue; and other, net.

No definition available.

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Ownership interest purchased.

No definition available.

Name:	wes_OwnershipInterestPurchased
Namespace Prefix:	wes_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	duration

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