Accumulated Other Comprehensive Income (Details) - CAD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Analysis Of Other Comprehensive Income By Item [Abstract]
Derivative financial instruments designated as cash flow hedges	$ 69	$ 71
Foreign currency translation adjustment	(61)	(37)
Accumulated other comprehensive income (loss)	$ 8	$ 34

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
-Number 1
-IssueDate 2020-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_55&doctype=Standard
-URIDate 2020-01-01

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