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ASSET RETIREMENT OBLIGATIONS (Tables) | 12 Months Ended
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Dec. 31, 2020
ASSET RETIREMENT OBLIGATIONS |
Schedule of reconciliation of asset retirement obligations | ​
​ | ​ | ​ | ​ | ​ | ​
​ | December 31, 2020 |  | December 31, 2019
Asset retirement obligation liability, beginning balance | $ | 32,201 | ​ | $ | 29,402
Settlements |  | (267) | ​ |  | (513)
Accretion of liability |  | 1,901 | ​ |  | 1,680
Adjustment reflecting updated estimates |  | (54) | ​ |  | 1,012
Foreign exchange revaluation | ​ | 219 | ​ | ​ | 620
Asset retirement obligation liability, ending balance | $ | 34,000 | ​ | $ | 32,201
Less current portion | ​ | 3,232 | ​ | ​ | 2,610
Long-term portion | $ | 30,768 | ​ | $ | 29,591
Schedule of reclamation expense | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | Year ended December 31,
​ | 2020 | ​ | 2019 | ​ | 2018
Reclamation adjustment reflecting updated estimates | $ | (113) | ​ | $ | 1,851 | ​ | $ | 2,259
Reclamation accretion | ​ | 1,901 | ​ | ​ | 1,680 | ​ | ​ | 1,205
Total | $ | 1,788 | ​ | ​ | 3,531 | ​ | $ | 3,464

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- Definition Tabular disclosure of the changes in carrying amount of a liability for asset retirement obligations, for changes such as new obligations, changes in estimates of existing obligations, spending on existing obligations, property dispositions, and foreign currency translation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13201-110859 + Details
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