Significant Accounting Policies - Schedule of Amounts Recorded in Prepaid Expenses and Other (Details) - USD ($) $ in Thousands |
Dec. 31, 2017 |
Dec. 31, 2016 |
|---|---|---|
| Prepaid Expense And Other Assets Current [Abstract] | ||
| Prepaid/accrued insurance | $ 2,401 | $ 2,924 |
| Surety bonds unamortized premiums | 2,676 | 2,462 |
| Prepaid deposits related to royalties | 6,456 | 6,237 |
| Other | 1,886 | 2,881 |
| Prepaid expenses and other | $ 13,419 | $ 14,504 |
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- Definition Amount of current assets classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of asset related to consideration paid in advance for insurance that provides economic benefits within a future period of one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of asset related to consideration paid in advance for royalties that provide economic benefits within a future period of one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Surety bond unamortized premiums. No definition available.
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