CHANGES IN OPERATING WORKING CAPITAL (Details) - CAD CAD in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
CHANGES IN OPERATING WORKING CAPITAL
Increase in Accounts receivable	CAD (573)	CAD (487)	CAD (19)
Increase in Inventories	(38)	(87)	(3)
Decrease/(increase) in Assets held for sale	14	(13)	0
Decrease/(increase) in Other current assets	189	328	(273)
Increase/(decrease) in Accounts payable and other	149	432	(103)
Increase in Accrued interest	12	62	91
(Decrease)/increase in Liabilities related to assets held for sale	(25)	16	0
(Increase)/decrease in Operating Working Capital	CAD (272)	CAD 251	CAD (307)

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- Definition

Increase (Decrease ) In Liabilities Related To Assets Held For Sale

+ References

No definition available.

+ Details

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- Definition

Amount of increase (decrease) in obligations incurred but not paid, and operating obligations classified as other.

+ References

No definition available.

+ Details

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- Definition

The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

+ References

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 period in book value of long-lived assets that the reporting entity plans to sell within one year (or one business cycle).

+ 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.

+ References

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- Definition

The increase (decrease) during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities.

+ References

+ Details

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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.

+ References

No definition available.

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