Other Income (Details) - CAD CAD in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
OTHER INCOME.
Unrealized (losses) recognized in earnings during the period	CAD (37)	CAD (47)
(Losses) gains on inventory valuation	(39)	62
Risk management activities	(19)	(25)
Investment and interest income	162	77
Risk mitigation and insurance proceeds	76	41
Change in value of pipeline commitments and other	(18)	53
Other income	CAD 125	CAD 161

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

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The amount of income arising from insurance contracts. [Refer: Types of insurance contracts [member]]

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The amount of operating income that the entity does not separately disclose in the same statement or note.

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The amount of change in value of pipeline commitments and other income.

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The amount of gains (losses) recognized in earnings from energy trading activities.

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The amount of gains lossess on inventory valuation from energy trading activities.

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The amount of income arising from investments and interest.

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