Notes Payable - Maturity table (Details) $ in Thousands  | 
3 Months Ended | 
|---|---|
| 
 Mar. 31, 2019  
USD ($) 
 | |
| Notes Payable | |
| Total | $ 14,835 | 
| Sweetwater IDR Bond [Member] | |
| Notes Payable | |
| Principal | 13,727 | 
| Interest | 1,108 | 
| 2017 | |
| Notes Payable | |
| Total | 4,450 | 
| 2017 | Sweetwater IDR Bond [Member] | |
| Notes Payable | |
| Principal | 3,914 | 
| Interest | 536 | 
| 2018 | |
| Notes Payable | |
| Total | 5,934 | 
| 2018 | Sweetwater IDR Bond [Member] | |
| Notes Payable | |
| Principal | 5,487 | 
| Interest | 447 | 
| 2019 | |
| Notes Payable | |
| Total | 4,451 | 
| 2019 | Sweetwater IDR Bond [Member] | |
| Notes Payable | |
| Principal | 4,326 | 
| Interest | $ 125 | 
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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 the required periodic payments including both interest and principal payments. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of the required periodic payments applied to interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of the required periodic payments applied to principal. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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