Debt and Interest Expense - Debt Outstanding Table (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Total short-term debt, principal	$ 2,714	$ 215,797
Total short-term debt, carrying value	2,714	215,780
Total long-term debt, carrying value	6,693,941	6,569,582
Valuation, Market Approach [Member] \| Level-2 Inputs [Member]
Debt Instrument [Line Items]
Short-term debt, fair value	2,714	217,482
Long-Term Debt Obligations [Member]
Debt Instrument [Line Items]
Total long-term debt, principal	6,756,246	6,633,271
Total long-term debt, carrying value	6,693,941	6,569,582
Long-Term Debt Obligations [Member] \| Valuation, Market Approach [Member] \| Level-2 Inputs [Member]
Debt Instrument [Line Items]
Long-term debt, fair value	6,194,431	5,897,794
WES Operating [Member]
Debt Instrument [Line Items]
Total short-term debt, carrying value	2,714	215,780
Total long-term debt, carrying value	6,693,941	6,569,582
WES Operating [Member] \| Finance Lease Liability, Short Term [Member]
Debt Instrument [Line Items]
Finance leases - short-term debt	2,714	2,659
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	2,714	2,659
WES Operating [Member] \| RCF [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Principal	495,000	375,000
Long-term debt, carrying value	495,000	375,000
WES Operating [Member] \| RCF [Member] \| Valuation, Market Approach [Member] \| Level-2 Inputs [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt, fair value	495,000	375,000
WES Operating [Member] \| Finance Lease Liability, Long Term [Member]
Debt Instrument [Line Items]
Finance leases - long-term debt	7,135	4,160
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	7,135	4,160
WES Operating [Member] \| Senior Notes [Member] \| Floating-Rate Senior Notes due 2023 [Member]
Debt Instrument [Line Items]
Principal	0	213,138
Short-term debt, carrying value	0	213,121
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	$ 0	214,823
WES Operating [Member] \| Senior Notes [Member] \| 3.100% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Senior note, interest rate	3.10%
Principal	$ 730,706	730,706
Long-term debt, carrying value	728,273	727,953
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	$ 703,032	692,491
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	397,056	396,825
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	$ 383,140	379,107
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	472,299	472,161
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	$ 459,488	452,201
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	396,840	396,698
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	$ 378,827	368,346
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	397,443	397,340
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	$ 381,273	368,141
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	1,191,606	1,191,345
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	$ 1,101,320	1,053,038
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	593,915	593,878
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	$ 524,661	503,742
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	687,553	687,494
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	$ 598,444	580,570
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	342,815	342,783
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	$ 302,297	291,194
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	984,006	983,945
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	$ 859,814	$ 829,804

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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