CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - CAD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Earnings/(loss)	$ (1,364)	$ 2,023
Other comprehensive income/(loss), net of tax
Change in unrealized loss on cash flow hedges	(513)	(192)
Change in unrealized gain/(loss) on net investment hedges	(715)	94
Other comprehensive income/(loss) from equity investees	(10)	12
Excluded components of fair value hedges	3	0
Reclassification to earnings of loss on cash flow hedges	32	11
Reclassification to earnings of pension and other postretirement benefits (OPEB) amounts	3	38
Foreign currency translation adjustments	5,637	(1,291)
Other comprehensive income/(loss), net of tax	4,437	(1,328)
Comprehensive income	3,073	695
Comprehensive (income)/loss attributable to noncontrolling interests	145	(13)
Comprehensive income attributable to controlling interests	2,928	708
Preference share dividends	(96)	(95)
Comprehensive income attributable to common shareholders	$ 2,832	$ 613