INTERIM CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - CAD CAD in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income	CAD 328	CAD 390	CAD 868	CAD 710
Net gain (loss) in foreign currency translation adjustments, net of hedging activities	3	7	40	(30)
Change in derivatives designated as cash flow hedges	(29)	36	(76)	(33)
Change in pension and post-retirement defined benefit plans	43	66	90	138
Other comprehensive income before income taxes	17	109	54	75
Income tax (expense) recovery on above items	(7)	(35)	(48)	11
Other comprehensive (loss) income	10	74	6	86
Comprehensive income	CAD 338	CAD 464	CAD 874	CAD 796

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831270

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=51831223

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans, attributable to parent entity.

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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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