Components of Working Capital - Accrued Liabilities Table (Details) - USD ($) $ in Thousands		Mar. 31, 2019	Dec. 31, 2018
Accrued interest expense		$ 55,831	$ 70,968
Short-term asset retirement obligations		23,033	25,938
Short-term remediation and reclamation obligations		863	863
Income taxes payable		861	384
Contract liabilities		6,364	16,235
Other	[1]	54,490	14,760
Total accrued liabilities	[2]	141,442	129,148	[3]
WES Operating [Member]
Accrued interest expense		55,831	70,959
Short-term asset retirement obligations		23,033	25,938
Short-term remediation and reclamation obligations		863	863
Income taxes payable		861	384
Contract liabilities		6,364	16,235
Other	[1]	54,315	13,495
Total accrued liabilities	[4]	$ 141,267	$ 127,874	[3]

[1] Includes amounts related to WES Operating’s interest-rate swaps as of March 31, 2019 and December 31, 2018 (see Note 10). Includes lease liabilities related to the implementation of ASU 2016-02, Leases (Topic 842) as of March 31, 2019 (see Note 1).

[2] Accrued liabilities includes affiliate amounts of $3.5 million and $2.2 million as of March 31, 2019, and December 31, 2018, respectively.

[3] Financial information has been recast to include the financial position and results attributable to AMA. See Note 1 and Note 3.

[4] Accrued liabilities includes affiliate amounts of $3.5 million and $2.2 million as of March 31, 2019, and December 31, 2018, respectively.