CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - CAD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 3,517	$ 2,852	$ 2,444
Net gain (loss) in foreign currency translation adjustments, net of hedging activities	1,628	(291)	18
Change in derivatives designated as cash flow hedges	6	48	10
Change in pension and post-retirement defined benefit plans	680	1,286	(407)
Equity accounted investments	(5)	9	(1)
Other comprehensive income (loss) before income taxes	2,309	1,052	(380)
Income tax (expense) recovery on above items	(115)	(341)	88
Other comprehensive income (loss)	2,194	711	(292)
Comprehensive income	$ 5,711	$ 3,563	$ 2,152