RECLAMATION AND REMEDIATION LIABILITIES - Reclamation and Remediation Liabilities rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Changes in the reclamation and remediation liability
Reclamation and remediation liabilities, beginning balance	$ 41,846	$ 35,452
Settlements	(1,358)	(774)
Accretion of liability	2,536	2,354
Revisions to estimates and discount rate	(300)	5,664
Foreign exchange revaluation	297	(850)
Reclamation and remediation liabilities, ending balance	43,021	41,846
Less: current portion	3,105	12,576
Long-term portion	39,916	29,270
Gold Bar Mine
Changes in the reclamation and remediation liability
Revisions to estimates and discount rate	1,500	3,200
Tonkin Properties
Changes in the reclamation and remediation liability
Revisions to estimates and discount rate	200	1,200
El Gallo Project
Changes in the reclamation and remediation liability
Revisions to estimates and discount rate	$ 1,600	$ 1,300

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 25
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481999/410-20-25-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481879/410-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
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Amount of foreign currency translation gain (loss) which decreases (increases) asset retirement obligations.

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- Definition

Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481850/410-20-50-1

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Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
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-Paragraph 1
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-URI https://asc.fasb.org//1943274/2147481850/410-20-50-1

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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