DEBT - Fair Value Adjustment (Details) - CAD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Debt Disclosure [Abstract]
Amortization of fair value adjustment	$ 12	$ 11	$ 34	$ 33