OTHER INCOME/(EXPENSE) (Details) - CAD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Other Income and Expenses [Abstract]
Realized foreign currency gain/(loss)	$ 121	$ (129)	$ 92
Unrealized foreign currency gain/(loss)	(2,199)	821	(1,094)
Net defined pension and OPEB credit	188	135	239
Other	564	397	174
Total	$ (1,326)	$ 1,224	$ (589)