RISK MANAGEMENT AND FINANCIAL INSTRUMENTS - Fair Value Derivatives (Details) - Fair Value Hedges - CAD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Foreign Currency Fair Value Hedge Derivative [Line Items]
Unrealized gain on derivative	$ 218	$ 0
Unrealized loss on hedged item	(203)	0
Realized loss on derivative	$ (12)	$ 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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- Definition

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 decrease in the fair value of derivatives recognized in the income statement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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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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