Selected Components of Working Capital - Accrued Liabilities Table (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accrued interest expense	$ 137,307	$ 72,064
Short-term asset retirement obligations	20,215	22,472
Short-term remediation and reclamation obligations	2,950	3,528
Income taxes payable	3,399	697
Contract liabilities	31,477	19,659
Other	74,599	31,373
Total accrued liabilities	269,947	149,793
WES Operating [Member]
Accrued interest expense	137,307	72,064
Short-term asset retirement obligations	20,215	22,472
Short-term remediation and reclamation obligations	2,950	3,528
Income taxes payable	3,399	697
Contract liabilities	31,477	19,659
Other	35,485	31,219
Total accrued liabilities	$ 230,833	$ 149,639