REVENUES - Contract Balances (Details) - CAD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Revenue from Contract with Customer [Abstract]
Contract Receivables	$ 2,161	$ 3,183
Contract Assets	230	230
Contract Liabilities	$ 2,448	$ 2,241

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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