Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Cost of product	[1]	$ 105,966	$ 239,223	$ 303,518	$ 631,859
Operation and maintenance	[1]	111,359	79,536	300,266	229,444
General and administrative	[1]	15,158	12,922	44,853	37,595
Affiliates [Member]
Cost of product	[2]	46,971	22,902	131,428	60,497
Operation and maintenance	[3]	25,145	18,110	68,830	53,661
General and administrative	[4]	$ 11,780	$ 10,414	$ 35,000	$ 29,637

[1] Cost of product includes product purchases from affiliates (as defined in Note 1) of $47.0 million and $131.4 million for the three and nine months ended September 30, 2018, respectively, and $22.9 million and $60.5 million for the three and nine months ended September 30, 2017, respectively. Operation and maintenance includes charges from affiliates of $25.1 million and $68.8 million for the three and nine months ended September 30, 2018, respectively, and $18.1 million and $53.7 million for the three and nine months ended September 30, 2017, respectively. General and administrative includes charges from affiliates of $11.8 million and $35.0 million for the three and nine months ended September 30, 2018, respectively, and $10.4 million and $29.6 million for the three and nine months ended September 30, 2017, respectively. See Note 6.

[2] Represents amounts earned or incurred on and subsequent to the date of the acquisition of WES assets, as well as amounts earned or incurred by Anadarko on a historical basis related to WES assets prior to the acquisition of such assets by WES, recognized under gathering, treating or processing agreements, and purchase and sale agreements.

[3] Represents expenses incurred on and subsequent to the date of the acquisition of WES assets, as well as expenses incurred by Anadarko on a historical basis related to WES assets prior to the acquisition of such assets by WES.

[4] Represents general and administrative expense incurred on and subsequent to the date of the acquisition of WES assets, as well as a management services fee for reimbursement of expenses incurred by Anadarko for periods prior to the acquisition of WES assets by WES. These amounts include equity-based compensation expense allocated to WES and WGP by Anadarko (see WES LTIP and Anadarko Incentive Plan within this Note 6) and amounts charged by Anadarko under the WGP and WES omnibus agreements.