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ASSET RETIREMENT OBLIGATIONS - Reclamation and Accretion (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2022 | Mar. 31, 2021
Reclamation obligations |  |
Reclamation adjustment reflecting updated estimates |  | $ 425
Reclamation accretion | $ 527 | 486
Total | $ 527 | $ 911

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- Definition Amount of reclamation adjustments during the period. + References No definition available. + Details
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- Definition Amount of reclamation and remediation expenses. + References No definition available. + Details
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- Definition Amount recognized for the passage of time, typically for liabilities, that have been discounted to their net present values. Excludes accretion associated with asset retirement obligations. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 35 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6394232&loc=d3e17558-110866 + Details
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