ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Details) - CAD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Analysis Of Other Comprehensive Income By Item [Abstract]
Derivative financial instruments designated as cash flow hedges	$ 47	$ 27
Foreign currency translation adjustment	(115)	43
Accumulated other comprehensive income (loss)	$ (68)	$ 70

The amount of accumulated items of income and expense (including reclassification adjustments) that are not recognised in profit or loss as required or permitted by other IFRSs. [Refer: IFRSs [member]; Other comprehensive income]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
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-IssueDate 2017-01-01
-Paragraph 55
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-URIDate 2017-03-09

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