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ASSET RETIREMENT OBLIGATIONS (Details) $ in Thousands, $ in Millions | 12 Months Ended
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Dec. 31, 2018 CAD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Reclamation obligations |  |  |  |
Reclamation Adjustment |  | $ 2,259 | $ 1,426 | $ 89
Remediation Accretion |  | 1,205 | 635 | 506
Reclamation and remediation expense |  | 3,464 | 2,061 | 595
Changes in the asset retirement obligations |  |  |  |
Asset retirement obligation, beginning of the period |  | 24,722 | 9,843 |
Settlements |  | (392) | (126) |
Accretion of liability |  | 1,205 | 635 |
Acquisitions and divestitures |  |  | 11,803 |
Adjustment reflecting updated estimates |  | 5,024 | 2,561 |
Foreign exchange revaluation |  | (1,157) | 6 |
Asset retirement obligation, ending balance |  | 29,402 | 24,722 | $ 9,843
Current portion |  | (734) | (646) |
Non-current portion |  | 28,668 | $ 24,076 |
Black Fox |  |  |  |
Mineral Property Interests |  |  |  |
Surety bonding obligation | $ 20.6 | 15,900 |  |
Changes in the asset retirement obligations |  |  |  |
Asset retirement obligation, ending balance |  | 11,200 |  |
Gold Bar project |  |  |  |
Changes in the asset retirement obligations |  |  |  |
Adjustment reflecting updated estimates |  | $ 3,700 |  |

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- Definition Represents a surety bond obligation. It is a promise by a surety or guarantor to pay one party (the obligee) a certain amount if a second party (the principal) fails to meet some obligation, such as fulfilling the terms of a contract. + 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://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 2: http://fasb.org/us-gaap/role/ref/legacyRef -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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- Definition 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
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- Definition 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
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- Definition Amount of foreign currency translation gain (loss) which decreases (increases) asset retirement obligations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
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- Definition 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 35 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6392603&loc=d3e7123-110846 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c)(4) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
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