CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - CAD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Earnings	$ 2,023	$ 510
Other comprehensive income/(loss), net of tax
Change in unrealized gain/(loss) on cash flow hedges	(192)
Change in unrealized gain/(loss) on cash flow hedges		66
Change in unrealized gain/(loss) on net investment hedges	94	(184)
Other comprehensive income from equity investees	12	14
Reclassification to earnings of (gain)/loss on cash flow hedges	11
Reclassification to earnings of (gain)/loss on cash flow hedges		37
Reclassification to earnings of pension and other postretirement benefits (OPEB) amounts	38	(39)
Foreign currency translation adjustments	(1,291)	1,579
Other comprehensive income/(loss), net of tax	(1,328)	1,473
Comprehensive income	695	1,983
Comprehensive (income)/loss attributable to noncontrolling interests and redeemable noncontrolling interests	13	(147)
Comprehensive income attributable to controlling interests	708	1,836
Preference share dividends	(95)	(89)
Comprehensive income attributable to common shareholders	$ 613	$ 1,747