v3.22.1

Debt and Interest Expense - Debt Outstanding Table (Details) - USD ($) $ in Thousands | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Debt Instrument [Line Items] |  |
Total short-term debt, principal | $ 718,585 | $ 506,040
Total short-term debt, carrying value | 718,153 | 505,932
Total long-term debt, carrying value | 6,188,750 | 6,400,616
Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Short-term debt, fair value | 717,876 | 508,947
Long-Term Debt Obligations [Member] |  |
Debt Instrument [Line Items] |  |
Total long-term debt, principal | 6,256,501 | 6,470,182
Total long-term debt, carrying value | 6,188,750 | 6,400,616
Long-Term Debt Obligations [Member] | Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, fair value | 6,272,959 | 7,284,665
WES Operating [Member] |  |
Debt Instrument [Line Items] |  |
Total short-term debt, carrying value | 718,153 | 505,932
Total long-term debt, carrying value | 6,188,750 | 6,400,616
WES Operating [Member] | Finance Lease Liability, Short Term [Member] |  |
Debt Instrument [Line Items] |  |
Finance leases - short-term debt | 3,201 | 3,794
WES Operating [Member] | Finance Lease Liability, Short Term [Member] | Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Finance leases - short-term debt | 3,201 | 3,794
WES Operating [Member] | Finance Lease Liability, Long Term [Member] |  |
Debt Instrument [Line Items] |  |
Finance leases - long-term debt | 990 | 1,533
WES Operating [Member] | Finance Lease Liability, Long Term [Member] | Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Finance leases - long-term debt | $ 990 | 1,533
WES Operating [Member] | Senior Notes [Member] | 4.000% Senior Notes due 2022 [Member] |  |
Debt Instrument [Line Items] |  |
Senior note, interest rate | 4.00% |
Principal | $ 502,246 | 502,246
Short-term debt, carrying value | 502,192 | 502,138
WES Operating [Member] | Senior Notes [Member] | 4.000% Senior Notes due 2022 [Member] | Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Short-term debt, fair value | 502,250 | 505,153
WES Operating [Member] | Senior Notes [Member] | Floating-Rate Senior Notes due 2023 [Member] |  |
Debt Instrument [Line Items] |  |
Principal | 213,138 | 213,138
Short-term debt, carrying value | 212,760 |
Long-term debt, carrying value | 212,760 | 212,642
WES Operating [Member] | Senior Notes [Member] | Floating-Rate Senior Notes due 2023 [Member] | Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Short-term debt, fair value | 212,425 |
Long-term debt, fair value | $ 212,425 | 213,072
WES Operating [Member] | Senior Notes [Member] | 3.100% Senior Notes due 2025 [Member] |  |
Debt Instrument [Line Items] |  |
Senior note, interest rate | 3.10% |
Principal | $ 732,106 | 732,106
Long-term debt, carrying value | 728,404 | 728,096
WES Operating [Member] | Senior Notes [Member] | 3.100% Senior Notes due 2025 [Member] | Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, fair value | $ 728,061 | 764,815
WES Operating [Member] | Senior Notes [Member] | 3.950% Senior Notes due 2025 [Member] |  |
Debt Instrument [Line Items] |  |
Senior note, interest rate | 3.95% |
Principal | $ 399,163 | 399,163
Long-term debt, carrying value | 396,149 | 395,928
WES Operating [Member] | Senior Notes [Member] | 3.950% Senior Notes due 2025 [Member] | Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, fair value | $ 402,063 | 418,506
WES Operating [Member] | Senior Notes [Member] | 4.650% Senior Notes due 2026 [Member] |  |
Debt Instrument [Line Items] |  |
Senior note, interest rate | 4.65% |
Principal | $ 474,242 | 474,242
Long-term debt, carrying value | 471,761 | 471,629
WES Operating [Member] | Senior Notes [Member] | 4.650% Senior Notes due 2026 [Member] | Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, fair value | $ 485,982 | 516,473
WES Operating [Member] | Senior Notes [Member] | 4.500% Senior Notes due 2028 [Member] |  |
Debt Instrument [Line Items] |  |
Senior note, interest rate | 4.50% |
Principal | $ 400,000 | 400,000
Long-term debt, carrying value | 396,281 | 396,145
WES Operating [Member] | Senior Notes [Member] | 4.500% Senior Notes due 2028 [Member] | Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, fair value | $ 407,380 | 437,673
WES Operating [Member] | Senior Notes [Member] | 4.750% Senior Notes due 2028 [Member] |  |
Debt Instrument [Line Items] |  |
Senior note, interest rate | 4.75% |
Principal | $ 400,000 | 400,000
Long-term debt, carrying value | 397,037 | 396,938
WES Operating [Member] | Senior Notes [Member] | 4.750% Senior Notes due 2028 [Member] | Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, fair value | $ 413,219 | 444,550
WES Operating [Member] | Senior Notes [Member] | 4.050% Senior Notes due 2030 [Member] |  |
Debt Instrument [Line Items] |  |
Senior note, interest rate | 4.05% |
Principal | $ 1,200,000 | 1,200,000
Long-term debt, carrying value | 1,190,584 | 1,190,339
WES Operating [Member] | Senior Notes [Member] | 4.050% Senior Notes due 2030 [Member] | Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, fair value | $ 1,201,380 | 1,323,595
WES Operating [Member] | Senior Notes [Member] | 5.450% Senior Notes due 2044 [Member] |  |
Debt Instrument [Line Items] |  |
Senior note, interest rate | 5.45% |
Principal | $ 600,000 | 600,000
Long-term debt, carrying value | 593,769 | 593,733
WES Operating [Member] | Senior Notes [Member] | 5.450% Senior Notes due 2044 [Member] | Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, fair value | $ 609,529 | 717,804
WES Operating [Member] | Senior Notes [Member] | 5.300% Senior Notes due 2048 [Member] |  |
Debt Instrument [Line Items] |  |
Senior note, interest rate | 5.30% |
Principal | $ 700,000 | 700,000
Long-term debt, carrying value | 687,321 | 687,265
WES Operating [Member] | Senior Notes [Member] | 5.300% Senior Notes due 2048 [Member] | Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, fair value | $ 694,990 | 844,223
WES Operating [Member] | Senior Notes [Member] | 5.500% Senior Notes due 2048 [Member] |  |
Debt Instrument [Line Items] |  |
Senior note, interest rate | 5.50% |
Principal | $ 350,000 | 350,000
Long-term debt, carrying value | 342,689 | 342,659
WES Operating [Member] | Senior Notes [Member] | 5.500% Senior Notes due 2048 [Member] | Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, fair value | $ 347,087 | 418,907
WES Operating [Member] | Senior Notes [Member] | 5.250% Senior Notes due 2050 [Member] |  |
Debt Instrument [Line Items] |  |
Senior note, interest rate | 5.25% |
Principal | $ 1,000,000 | 1,000,000
Long-term debt, carrying value | 983,765 | 983,709
WES Operating [Member] | Senior Notes [Member] | 5.250% Senior Notes due 2050 [Member] | Valuation, Market Approach [Member] | Level-2 Inputs [Member] |  |
Debt Instrument [Line Items] |  |
Long-term debt, fair value | $ 982,278 | $ 1,183,514

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