INTERIM CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - CAD CAD in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income	CAD 510	CAD 347	CAD 1,421	CAD 1,215
Net gain (loss) in foreign currency translation adjustments, net of hedging activities	19	(7)	38	33
Change in derivatives designated as cash flow hedges	2	1	11	(75)
Change in pension and post-retirement defined benefit plans	38	47	113	137
Other comprehensive income before income taxes	59	41	162	95
Income tax (expense) recovery on above items	(34)	(3)	(78)	(51)
Other comprehensive income (loss)	25	38	84	44
Comprehensive income	CAD 535	CAD 385	CAD 1,505	CAD 1,259

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount before tax, after reclassification adjustments of gain (loss) on foreign currency translation adjustments, on foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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Amount before tax of other comprehensive income (loss) attributable to parent entity.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

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