RISK MANAGEMENT AND FINANCIAL INSTRUMENTS - Fair Value Derivatives (Details) - CAD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
RISK MANAGEMENT AND FINANCIAL INSTRUMENTS
Realized gain/(loss) on derivative	$ 23	$ (97)	$ (431)
Interest rate contracts \| Fair value hedges
RISK MANAGEMENT AND FINANCIAL INSTRUMENTS
Unrealized loss on derivative	(3)	(132)
Unrealized gain on hedged item	6	131
Realized gain/(loss) on derivative	26	(47)
Realized loss on hedged item	$ (79)	$ 0

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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