REVENUE - Contract Balances (Details) - CAD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Revenue from Contract with Customer [Abstract]
Contract Receivables	$ 2,962	$ 2,802
Contract Assets	337	400
Contract Liabilities	$ 2,537	$ 2,591

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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