Mineral Properties (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | |
|---|---|---|---|
Sep. 30, 2014 |
Sep. 30, 2015 |
Sep. 30, 2014 |
|
| Mineral Properties, Rollforward | |||
| Balance, beginning of period | $ 52,750 | $ 5,700 | |
| Acquisition costs | 1 | ||
| Increase in reclamation costs | 1,460 | ||
| Property write-offs | $ (329) | $ (422) | |
| Amortization | (3,651) | ||
| Balance, end of period | 50,560 | ||
| Lost Creek Property [Member] | |||
| Mineral Properties, Rollforward | |||
| Balance, beginning of period | 18,512 | ||
| Increase in reclamation costs | 1,460 | ||
| Amortization | (3,651) | ||
| Balance, end of period | 16,321 | ||
| Path Finder Mines [Member] | |||
| Mineral Properties, Rollforward | |||
| Balance, beginning of period | 21,028 | ||
| Acquisition costs | 1 | ||
| Balance, end of period | 21,029 | ||
| Other US Properties [Member] | |||
| Mineral Properties, Rollforward | |||
| Balance, beginning of period | 13,210 | ||
| Balance, end of period | $ 13,210 | ||
| X | ||||||||||
- Definition The assumption amount in estimated asset reclamation obligation. No definition available.
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition The capitalized costs incurred during the period (excluded from amortization) to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Mineral properties, net of adjustments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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