INCOME TAXES - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Components of Deferred Tax Assets [Abstract]
Inventories	$ 547	$ 5,984
Short-term investments	209	209
Operating loss carry forwards	93,241	108,827
Capital loss carry forwards	849	881
Deferred revenue and other	2,431	5,433
Mineral properties and deferred costs, United States	16,872	18,727
Mineral properties and deferred costs, Canada	1,726	1,815
Asset retirement obligations	2,894	3,976
Property, plant and equipment	986	1,079
Total deferred tax assets	119,755	146,931
Less: valuation allowance	(119,755)	(146,931)
Net deferred tax assets	$ 0	$ 0

Deferred Tax Assets, Deferred Income and Other, Noncurrent

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Deferred Tax Assets, Mineral Properties and Deferred Costs, Canada

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible capital loss carryforwards.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-6

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from investments (excludes investments in subsidiaries and equity method investments).

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from property, plant, and equipment.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from asset retirement obligations. An asset retirement obligation is a legal obligation associated with the disposal or retirement from service of a tangible long-lived asset.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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