Inventory (Details) - USD ($) $ in Thousands  | 
3 Months Ended | 9 Months Ended | |
|---|---|---|---|
Sep. 30, 2019  | 
Sep. 30, 2019  | 
Dec. 31, 2018  | 
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| Inventory | |||
| Inventory, Net, Total | $ 7,357 | $ 7,357 | $ 14,692 | 
| Inventory Current | 1,840 | ||
| Inventory, Noncurrent | 7,357 | 7,357 | 12,852 | 
| Reduction in inventory valuation | 4,087 | 8,189 | |
| In Process Inventory [Member] | |||
| Inventory | |||
| Inventory, Net, Total | 160 | ||
| Plant Inventory [Member] | |||
| Inventory | |||
| Inventory, Net, Total | 384 | 384 | 345 | 
| Conversion Facility Inventory [Member] | |||
| Inventory | |||
| Inventory, Net, Total | $ 6,973 | $ 6,973 | $ 14,187 | 
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- Definition Inventory to be sold within 12 months No definition available. 
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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 after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Inventories not expected to be converted to cash, sold or exchanged within the normal operating cycle. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of increase (decrease) in valuation and qualifying accounts and reserves. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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