INCOME AND MINING TAXES - Deferred Income Tax Recovery (Expense) and Net Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Current tax (expense)/recovery
Foreign	$ 7,663
Current tax expense	7,663
Deferred income tax (expense)/recovery
United States		$ (387)	$ (817)
Foreign	(1,856)	(6,928)	(573)
Deferred tax recovery	(1,856)	(7,315)	(1,390)
Mining Tax Expense Recovery [Abstract]
United States		(387)	(817)
Foreign	5,806	(6,928)	(573)
Total income and mining tax expense/(recovery)	5,806	(7,315)	(1,390)
Net income (loss) before tax:
United States	(20,618)	(24,808)	(127,524)
Foreign	(59,670)	(39,391)	(26,191)
Loss before income and mining taxes	$ (80,288)	$ (64,199)	$ (153,715)

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The Amount of income and mining current foreign tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, current national tax expense (benefit) for non-US (United States of America) jurisdiction.

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The Amount of income and mining current federal tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, current national tax expense (benefit) for non-US (United States of America) jurisdiction.

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Amount of current foreign income tax expense (benefit) pertaining to income (loss) from continuing operations.

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The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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