Derivative Losses (Details) - CAD CAD in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Analysis of income and expense [abstract]
Realized gains	CAD 101.2	CAD 468.7
Unrealized losses	(163.6)	(706.8)
Derivative losses	CAD (62.4)	CAD (238.1)

The gains (losses) resulting from change in the fair value of derivatives recognised in profit or loss. [Refer: Derivatives [member]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-URIDate 2017-03-09

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