CHANGE IN OPERATING WORKING CAPITAL - Components (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
CHANGE IN OPERATING WORKING CAPITAL
Change in accounts receivable and other	$ 2	$ 11
Change in other current assets	(1)	2
Change in accounts payable and accrued liabilities	(6)	(5)
Change in accounts payable to affiliates		(2)
Change in accrued interest		1
Change in operating working capital	$ (5)	$ 7

The increase (decrease) during the reporting period in the amounts payable to vendors for goods and services received and the amount of obligations and expenses incurred but not paid.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

The increase (decrease) during the reporting period in the obligations due for goods and services provided by the following types of related parties: a parent company and its subsidiaries, subsidiaries of a common parent, an entity and trust for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entities' management, an entity and its principal owners, management, or member of their immediate families, affiliates, or other parties with the ability to exert significant influence.

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- Definition

Amount of increase (decrease) in receivables, and operating assets classified as other.

+ References

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- Definition

The increase (decrease) during the reporting period in interest payable, which represents the amount owed to note holders, bond holders, and other parties for interest earned on loans or credit extended to the reporting entity.

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- Definition

The increase (decrease) during the reporting period of all assets and liabilities used in operating activities.

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- Definition

Amount of increase (decrease) in current assets classified as other.

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