Restricted Cash (Details) - USD ($) |
Dec. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Restricted Cash | ||
| Restricted cash | $ 7,458,000 | $ 7,558,000 |
| Reclamation bonding requirement | 29,880,000 | |
| Certificate of deposit [Member] | ||
| Restricted Cash | ||
| Restricted cash | 100,000 | |
| Money Market Funds [Member] | ||
| Restricted Cash | ||
| Restricted cash | 7,458,000 | $ 7,458,000 |
| Money Market Funds [Member] | Surety Bond [Member] | ||
| Restricted Cash | ||
| Restricted cash pledged as collateral | $ 7,444,000 |
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- Definition Represents the amount of reclamation obligations, which are required to be covered by surety performance bonding, as of the balance sheet date. No definition available.
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- Definition The sum of the fair values, as of the date of each statement of financial position presented, of securities that are restricted as collateral for the payment of related debt obligations, primarily secured borrowings and repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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