Consolidated Balance Sheets - WES Operating - USD ($) $ in Thousands		Dec. 31, 2020	Dec. 31, 2019
Current assets
Cash and cash equivalents		$ 444,922	$ 99,962
Accounts receivable, net		452,880	260,512
Other current assets		45,262	41,938
Total current assets		943,064	402,412
Property, plant, and equipment
Cost		12,641,745	12,355,671
Less accumulated depreciation		3,931,800	3,290,740
Net property, plant, and equipment		8,709,945	9,064,931
Goodwill		4,783	445,800
Other intangible assets		776,409	809,391
Equity investments		1,224,813	1,285,717
Other assets	[1]	171,013	78,202
Total assets	[2]	11,830,027	12,346,453
Current liabilities
Accounts and imbalance payables		210,691	293,128
Short-term debt		438,870	7,873
Accrued ad valorem taxes		41,427	35,160
Accrued liabilities		269,947	149,793
Total current liabilities		960,935	485,954
Long-term liabilities
Long-term debt		7,415,832	7,951,565
Deferred income taxes		22,195	18,899
Asset retirement obligations		260,283	336,396
Other liabilities		275,570	208,346
Total long-term liabilities		7,973,880	8,515,206
Total liabilities	[3]	8,934,815	9,001,160
Equity and partners' capital
Common units (318,675,578 units issued and outstanding at December 31, 2020 and 2019)		2,778,339	3,209,947
Total partners' capital		2,761,131	3,195,723
Noncontrolling interest		134,081	149,570
Total equity and partners' capital		2,895,212	3,345,293
Total liabilities, equity, and partners' capital		$ 11,830,027	$ 12,346,453
Common units issued		413,839,863	443,971,409
Common units outstanding		413,839,863	443,971,409
Related Parties [Member]
Current assets
Accounts receivable, net		$ 291,253	$ 113,345
Other current assets		5,493	4,982
Anadarko note receivable		0	260,000
Property, plant, and equipment
Other assets		50,967	60,221
Total assets		1,572,526	1,724,265
Current liabilities
Accounts and imbalance payables		6,664	0
Accrued liabilities		19,195	3,087
Long-term liabilities
Other liabilities		138,796	97,800
Total liabilities		164,655	108,760
WES Operating [Member]
Current assets
Cash and cash equivalents		418,537	98,122
Accounts receivable, net		407,549	260,748
Other current assets		43,244	39,914
Total current assets		869,330	398,784
Property, plant, and equipment
Cost		12,641,745	12,355,671
Less accumulated depreciation		3,931,800	3,290,740
Net property, plant, and equipment		8,709,945	9,064,931
Goodwill		4,783	445,800
Other intangible assets		776,409	809,391
Equity investments		1,224,813	1,285,717
Other assets	[4]	171,013	78,202
Total assets	[5]	11,756,293	12,342,825
Current liabilities
Accounts and imbalance payables		210,532	293,128
Short-term debt		438,870	7,873
Accrued ad valorem taxes		41,427	35,160
Accrued liabilities		230,833	149,639
Total current liabilities		921,662	485,800
Long-term liabilities
Long-term debt		7,415,832	7,951,565
Deferred income taxes		22,195	18,899
Asset retirement obligations		260,283	336,396
Other liabilities		275,570	208,346
Total long-term liabilities		7,973,880	8,515,206
Total liabilities	[6]	8,895,542	9,001,006
Equity and partners' capital
Common units (318,675,578 units issued and outstanding at December 31, 2020 and 2019)		2,831,199	3,286,620
Total partners' capital		2,831,199	3,286,620
Noncontrolling interest		29,552	55,199
Total equity and partners' capital		2,860,751	3,341,819
Total liabilities, equity, and partners' capital		$ 11,756,293	$ 12,342,825
Common units issued		318,675,578	318,675,578
Common units outstanding		318,675,578	318,675,578
WES Operating [Member] | Related Parties [Member]
Current assets
Accounts receivable, net		$ 246,083	$ 113,581
Anadarko note receivable		0	260,000
Property, plant, and equipment
Total assets		1,500,000	1,700,000
Long-term liabilities
Total liabilities		$ 164,300	$ 108,800

[1] Other assets includes $4.2 million and $4.5 million of NGLs line-fill inventory as of December 31, 2020 and 2019, respectively. Other assets also includes $71.9 million of materials and supplies inventory as of December 31, 2020. See Note 1.

[2] Total assets includes related-party amounts of $1.6 billion and $1.7 billion as of December 31, 2020 and 2019, respectively, which includes related-party Accounts receivable, net of $291.3 million and $113.3 million as of December 31, 2020 and 2019, respectively. See Note 6.

[3] Total liabilities includes related-party amounts of $164.7 million and $108.8 million as of December 31, 2020 and 2019, respectively. See Note 6.

[4] Other assets includes $4.2 million and $4.5 million of NGLs line-fill inventory as of December 31, 2020 and 2019, respectively. Other assets also includes $71.9 million of materials and supplies inventory as of December 31, 2020. See Note 1.

[5] Total assets includes related-party amounts of $1.5 billion and $1.7 billion as of December 31, 2020 and 2019, respectively, which includes related-party Accounts receivable, net of $246.1 million and $113.6 million as of December 31, 2020 and 2019, respectively. See Note 6.

[6] Total liabilities includes related-party amounts of $164.3 million and $108.8 million as of December 31, 2020 and 2019, respectively. See Note 6.