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

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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