Debt and Interest Expense - Debt Outstanding Table (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Total short-term debt, principal	$ 108,461	$ 621,321
Total short-term debt, carrying value	108,394	617,748
Total long-term debt, carrying value	7,272,079	7,283,556
Valuation, Market Approach [Member] \| Level-2 Inputs [Member]
Debt Instrument [Line Items]
Short-term debt, fair value	108,394	617,748
Long-Term Debt Obligations [Member]
Debt Instrument [Line Items]
Total long-term debt, principal	7,342,709	7,356,091
Total long-term debt, carrying value	7,272,079	7,283,556
Long-Term Debt Obligations [Member] \| Valuation, Market Approach [Member] \| Level-2 Inputs [Member]
Debt Instrument [Line Items]
Long-term debt, fair value	6,975,839	7,011,688
WES Operating [Member]
Debt Instrument [Line Items]
Total short-term debt, carrying value	108,394	617,748
Total long-term debt, carrying value	7,272,079	7,283,556
WES Operating [Member] \| Commercial Paper Program \| Commercial Paper Program
Debt Instrument [Line Items]
Principal	100,000	613,885
Commercial paper, carrying value	99,933	610,312
WES Operating [Member] \| Commercial Paper Program \| Valuation, Market Approach [Member] \| Level-2 Inputs [Member] \| Commercial Paper Program
Debt Instrument [Line Items]
Short-term debt, fair value	99,933	610,312
WES Operating [Member] \| Finance Lease Liability, Short Term [Member]
Debt Instrument [Line Items]
Finance leases - short-term debt	8,461	7,436
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	8,461	7,436
WES Operating [Member] \| Finance Lease Liability, Long Term [Member]
Debt Instrument [Line Items]
Finance leases - long-term debt	30,394	28,668
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	$ 30,394	28,668
WES Operating [Member] \| Senior Notes [Member] \| 3.100% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Senior note, interest rate	3.10%
Principal	$ 663,831	666,481
Long-term debt, carrying value	662,804	665,145
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	$ 649,658	650,765
WES Operating [Member] \| Senior Notes [Member] \| 3.950% Senior Notes due 2025 [Member]
Debt Instrument [Line Items]
Senior note, interest rate	3.95%
Principal	$ 348,645	349,163
Long-term debt, carrying value	347,631	347,938
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	$ 341,763	341,415
WES Operating [Member] \| Senior Notes [Member] \| 4.650% Senior Notes due 2026 [Member]
Debt Instrument [Line Items]
Senior note, interest rate	4.65%
Principal	$ 467,204	467,204
Long-term debt, carrying value	465,848	465,705
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	$ 458,425	459,617
WES Operating [Member] \| Senior Notes [Member] \| 4.500% Senior Notes due 2028 [Member]
Debt Instrument [Line Items]
Senior note, interest rate	4.50%
Principal	$ 350,175	357,094
Long-term debt, carrying value	347,923	354,665
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	$ 338,199	346,121
WES Operating [Member] \| Senior Notes [Member] \| 4.750% Senior Notes due 2028 [Member]
Debt Instrument [Line Items]
Senior note, interest rate	4.75%
Principal	$ 381,848	382,888
Long-term debt, carrying value	379,816	380,747
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	$ 370,935	374,767
WES Operating [Member] \| Senior Notes [Member] \| 6.350% Senior Notes due 2029 [Member]
Debt Instrument [Line Items]
Senior note, interest rate	6.35%
Principal	$ 600,000	600,000
Long-term debt, carrying value	593,364	593,069
WES Operating [Member] \| Senior Notes [Member] \| 6.350% Senior Notes due 2029 [Member] \| Valuation, Market Approach [Member] \| Level-2 Inputs [Member]
Debt Instrument [Line Items]
Long-term debt, fair value	$ 622,248	626,994
WES Operating [Member] \| Senior Notes [Member] \| 4.050% Senior Notes due 2030 [Member]
Debt Instrument [Line Items]
Senior note, interest rate	4.05%
Principal	$ 1,100,612	1,104,593
Long-term debt, carrying value	1,093,906	1,097,609
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	$ 1,025,726	1,036,097
WES Operating [Member] \| Senior Notes [Member] \| 6.150% Senior Notes due 2033 [Member]
Debt Instrument [Line Items]
Senior note, interest rate	6.15%
Principal	$ 750,000	750,000
Long-term debt, carrying value	741,302	741,125
WES Operating [Member] \| Senior Notes [Member] \| 6.150% Senior Notes due 2033 [Member] \| Valuation, Market Approach [Member] \| Level-2 Inputs [Member]
Debt Instrument [Line Items]
Long-term debt, fair value	$ 769,373	780,203
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	594,070	594,031
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	$ 551,802	545,154
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	687,798	687,735
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	$ 611,492	614,082
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	342,947	342,913
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	$ 310,674	312,365
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	984,276	984,206
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	$ 895,150	$ 895,440

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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