INTERIM CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - CAD ($) shares in Millions, $ in Millions	Total	Parent	Share capital	Additional paid-in capital	Accumulated other comprehensive income (loss)	Retained earnings	Non-controlling interest
Beginning balance (shares) at Dec. 31, 2021	929.7
Beginning balance at Dec. 31, 2021	$ 33,829	$ 33,829	$ 25,475	$ 66	$ (2,103)	$ 10,391	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,355	1,355				1,355
Other Comprehensive Income (Loss), Net of Tax	564	564			564
Other comprehensive income (loss)	564
Dividends declared	(354)	(354)				(354)
Effect of stock-based compensation expense	12	12		12
Shares issued for Kansas City Southern acquisition	$ (2)	(2)
Shares issued under stock option plan (shares)	0.3
Shares issued under stock option plan	$ 10	10	13	(3)
Ending balance (shares) at Jun. 30, 2022	930.0
Ending balance at Jun. 30, 2022	$ 35,414	35,414	25,488	73	(1,539)	11,392	0
Beginning balance (shares) at Mar. 31, 2022	929.9
Beginning balance at Mar. 31, 2022	$ 33,985	33,985	25,486	68	(2,373)	10,804	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	765	765				765
Other Comprehensive Income (Loss), Net of Tax	834	834			834
Other comprehensive income (loss)	834
Dividends declared	(177)	(177)				(177)
Effect of stock-based compensation expense	$ 5	5		5
Shares issued under stock option plan (shares)	0.1
Shares issued under stock option plan	$ 2	2	2
Ending balance (shares) at Jun. 30, 2022	930.0
Ending balance at Jun. 30, 2022	$ 35,414	35,414	25,488	73	(1,539)	11,392	0
Beginning balance (shares) at Dec. 31, 2022	930.5
Beginning balance at Dec. 31, 2022	$ 38,886	38,886	25,516	78	91	13,201	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,125	2,124				2,124	1
Other Comprehensive Income (Loss), Net of Tax	(643)	(635)			(635)		(8)
Other comprehensive income (loss)	(635)
Dividends declared	(353)	(353)				(353)
Effect of stock-based compensation expense	$ 19	19		19
Shares issued under stock option plan (shares)	0.9
Shares issued under stock option plan	$ 38	38	47	(9)
Non-controlling interest in connection with business acquisition	$ 932						932
Ending balance (shares) at Jun. 30, 2023	931.4
Ending balance at Jun. 30, 2023	$ 41,004	40,079	25,563	88	(544)	14,972	925
Beginning balance (shares) at Mar. 31, 2023	930.9
Beginning balance at Mar. 31, 2023	$ 39,520	39,520	25,538	84	74	13,824	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,325	1,324				1,324	1
Other Comprehensive Income (Loss), Net of Tax	(626)	(618)			(618)		(8)
Other comprehensive income (loss)	(618)
Dividends declared	(176)	(176)				(176)
Effect of stock-based compensation expense	$ 9	9		9
Shares issued under stock option plan (shares)	0.5
Shares issued under stock option plan	$ 20	20	25	(5)
Non-controlling interest in connection with business acquisition	$ 932						932
Ending balance (shares) at Jun. 30, 2023	931.4
Ending balance at Jun. 30, 2023	$ 41,004	$ 40,079	$ 25,563	$ 88	$ (544)	$ 14,972	$ 925