FOREIGN EXCHANGE (Details) - CAD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
FOREIGN EXCHANGE
Foreign exchange (gain)/loss	$ (87)	$ 523	$ 1,495
Translation of U.S. dollar cash held in Canada (gain)/loss	8,794	(19,630)	10,978
Translation of U.S. dollar debt and working capital (gain)/loss	(34,085)	58,628	(42,623)
Foreign exchange (gain)/loss	$ (25,378)	$ 39,521	$ (30,150)

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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