Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Contractual interest rate for funds borrowed, under the debt agreement.

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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 total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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No definition available.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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The effective interest rate at the end of the reporting period.

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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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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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The amount to which the maximum borrowing capacity under the credit facility could be expanded 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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No definition available.

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Debt and Interest Expense - Additional Information (Details) - WES Operating [Member] - USD ($)	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Mar. 31, 2021
3.100% Senior Notes due 2025 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Senior note, interest rate	3.10%
Senior note, effective interest rate	3.79%	4.542%
Repayments of senior notes	$ 1,400,000
4.050% Senior Notes due 2030 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Senior note, interest rate	4.05%
Senior note, effective interest rate	4.671%	5.424%
5.250% Senior Notes due 2050 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Senior note, interest rate	5.25%
Senior note, effective interest rate	5.869%	6.629%
Floating-Rate Senior Notes due 2023 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Senior note, effective interest rate	2.12%	2.29%
4.000% Senior Notes due 2022 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Senior note, interest rate	4.00%
Repayments of senior notes	$ 502,246,000
5.375% Senior Notes due 2021 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Senior note, interest rate			5.375%
RCF [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Facility, maximum borrowing capacity	2,000,000,000
Facility, expandable maximum borrowing capacity	2,500,000,000
Facility, outstanding borrowings	255,000,000
Facility, outstanding letters of credit	5,200,000
Facility, available borrowing capacity	$ 1,700,000,000
Facility, interest rate at period end	3.12%	1.60%
Facility, fee rate	0.25%	0.25%
RCF [Member] \| Revolving Credit Facility [Member] \| Extending Lenders [Member]
Debt Instrument [Line Items]
Facility, borrowing capacity for extending and non-extending lender	$ 1,600,000,000
RCF [Member] \| Revolving Credit Facility [Member] \| Non-Extending Lenders [Member]
Debt Instrument [Line Items]
Facility, borrowing capacity for extending and non-extending lender	$ 400,000,000