CHANGE IN OPERATING WORKING CAPITAL (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Supplemental Cash Flow Elements [Abstract]
Change in accounts receivable and other	$ 3	$ 7
Change in inventories	(1)	(1)
Change in other current assets	3	2
Change in accounts payable and accrued liabilities	(3)	(4)
Change in accounts payable to affiliates	(2)	1
Change in accrued interest	9	8
Change in operating working capital	$ 9	$ 13