INTERIM CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - CAD ($) shares in Millions, $ in Millions	Total	Total shareholders’ equity	Share capital	Additional paid-in capital	Accumulated other comprehensive income (loss)	Retained earnings	Non-controlling interest
Beginning balance (shares) at Dec. 31, 2023			932.1
Beginning balance at Dec. 31, 2023	$ 42,411	$ 41,492	$ 25,602	$ 88	$ (618)	$ 16,420	$ 919
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	1,677	1,680				1,680	(3)
Contribution from non-controlling interest	1						1
Other comprehensive income (loss)	1,031	997			997		34
Dividends declared	(355)	(355)				(355)
Effect of stock-based compensation expense	16	16		16
Stock Issued During Period, Value, Stock Options Exercised	42	42	$ 53	(11)
Shares issued under stock option plan (shares)			1.0
Ending balance (shares) at Jun. 30, 2024			933.1
Ending balance at Jun. 30, 2024	44,823	43,872	$ 25,655	93	379	17,745	951
Beginning balance (shares) at Mar. 31, 2024			932.6
Beginning balance at Mar. 31, 2024	43,761	42,819	$ 25,629	95	77	17,018	942
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	903	905				905	(2)
Other comprehensive income (loss)	313	302			302		11
Dividends declared	(178)	(178)				(178)
Effect of stock-based compensation expense	3	3		3
Shares issued under stock option plan (shares)			0.5
Shares issued under stock option plan	21	21	$ 26	(5)
Ending balance (shares) at Jun. 30, 2024			933.1
Ending balance at Jun. 30, 2024	44,823	43,872	$ 25,655	93	379	17,745	951
Beginning balance (shares) at Dec. 31, 2024			933.5
Beginning balance at Dec. 31, 2024	48,890	47,892	$ 25,689	94	2,680	19,429	998
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	2,143	2,144				2,144	(1)
Contribution from non-controlling interest	1						1
Other comprehensive income (loss)	(1,784)	(1,729)			(1,729)		(55)
Dividends declared	(387)	(387)				(387)
Effect of stock-based compensation expense	20	20		20
Common Shares repurchased (in shares)			(16.4)
Common Shares repurchased	(1,773)	(1,773)	$ (450)			(1,323)
Shares issued under stock option plan (shares)			0.8
Shares issued under stock option plan	37	37	$ 46	(9)
Ending balance (shares) at Jun. 30, 2025			917.9
Ending balance at Jun. 30, 2025	47,147	46,204	$ 25,285	105	951	19,863	943
Beginning balance (shares) at Mar. 31, 2025			930.4
Beginning balance at Mar. 31, 2025	49,243	48,246	$ 25,603	107	2,653	19,883	997
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	1,234	1,234				1,234
Other comprehensive income (loss)	(1,756)	(1,702)			(1,702)		(54)
Dividends declared	(210)	(210)				(210)
Effect of stock-based compensation expense	4	4		4
Common Shares repurchased (in shares)			(13.1)
Common Shares repurchased	(1,398)	(1,398)	$ (354)			(1,044)
Shares issued under stock option plan (shares)			0.6
Shares issued under stock option plan	30	30	$ 36	(6)
Ending balance (shares) at Jun. 30, 2025			917.9
Ending balance at Jun. 30, 2025	$ 47,147	$ 46,204	$ 25,285	$ 105	$ 951	$ 19,863	$ 943