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

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

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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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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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Weighted average interest rate of debt outstanding.

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No definition available.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

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

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No definition available.

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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.

+ References

No definition available.

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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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Amount of cash outflow for short-term and long-term debt. Excludes payment of lease obligation.

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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) - USD ($)	1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 30, 2024	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Debt Instrument [Line Items]
Gain (loss) on early extinguishment of debt		$ 524,000	$ 0
WES Operating [Member]
Debt Instrument [Line Items]
Gain (loss) on early extinguishment of debt		524,000	$ 0
WES Operating [Member] \| 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		0
Facility, outstanding letters of credit		500,000
Facility, available borrowing capacity		$ 1,900,000,000
Facility, interest rate at period end		6.63%	6.21%
Facility, fee rate		0.20%
WES Operating [Member] \| Commercial Paper Program \| Commercial Paper Program
Debt Instrument [Line Items]
Principal amount		$ 100,000,000		$ 613,885,000
Facility, maximum borrowing capacity		$ 2,000,000,000
Commercial paper, weighted average interest rate		6.00%
WES Operating [Member] \| Commercial Paper Program \| Commercial Paper Program \| Maximum [Member]
Debt Instrument [Line Items]
Commercial paper, term		397 days
WES Operating [Member] \| Commercial Paper Program \| Commercial Paper Program \| Weighted Average [Member]
Debt Instrument [Line Items]
Commercial paper, term		4 days
WES Operating [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Repayments of senior notes		$ 15,100,000		276,700,000
Gain (loss) on early extinguishment of debt		$ 500,000
WES Operating [Member] \| Senior Notes [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Repayments of senior notes	$ 134,900,000
WES Operating [Member] \| Senior Notes [Member] \| 3.100% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Senior note, interest rate		3.10%
Senior note, effective interest rate		3.29%	3.79%
Principal amount		$ 663,831,000		666,481,000
Repayments of senior notes		$ 2,650,000
WES Operating [Member] \| Senior Notes [Member] \| 4.050% Senior Notes due 2030 [Member]
Debt Instrument [Line Items]
Senior note, interest rate		4.05%
Senior note, effective interest rate		4.169%	4.671%
Principal amount		$ 1,100,612,000		1,104,593,000
Repayments of senior notes		$ 3,981,000
WES Operating [Member] \| Senior Notes [Member] \| 5.250% Senior Notes due 2050 [Member]
Debt Instrument [Line Items]
Senior note, interest rate		5.25%
Senior note, effective interest rate		5.363%	5.869%
Principal amount		$ 1,000,000,000		1,000,000,000
WES Operating [Member] \| Senior Notes [Member] \| 6.350% Senior Notes due 2029 [Member]
Debt Instrument [Line Items]
Senior note, interest rate		6.35%
Principal amount		$ 600,000,000		600,000,000
WES Operating [Member] \| Senior Notes [Member] \| 6.150% Senior Notes due 2033 [Member]
Debt Instrument [Line Items]
Senior note, interest rate		6.15%
Principal amount		$ 750,000,000		$ 750,000,000