REVENUE - Schedule of Contract Balances (Details) - CAD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Revenue from Contract with Customer [Abstract]
Contract Receivables	$ 4,207	$ 3,764
Contract Assets	323	330
Contract Liabilities	$ 2,728	$ 2,828

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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