RISK MANAGEMENT AND FINANCIAL INSTRUMENTS - Fair Value Derivatives (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
RISK MANAGEMENT AND FINANCIAL INSTRUMENTS
Realized loss on derivative	$ (97)	$ (431)	$ 59
Interest rate contracts \| Fair value hedges
RISK MANAGEMENT AND FINANCIAL INSTRUMENTS
Unrealized gain/(loss) on derivative	(132)	262
Unrealized gain/(loss) on hedged item	131	(254)
Realized loss on derivative	(47)	(110)
Realized gain on hedged item	$ 0	$ 85

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Gain (loss) incurred in hedging activities.

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