Property, plant and equipment -Depreciation (Details) - USD ($)  | 
12 Months Ended | |
|---|---|---|
Dec. 31, 2017  | 
Dec. 31, 2016  | 
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| Property, Plant and Equipment [Abstract] | ||
| Depreciation and amortization | $ 1,114,540 | $ 165,695 | 
| X | ||||||||||
- Definition Depreciation, Depletion and Amortization, Property, Plant and Equipment No definition available. 
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| X | ||||||||||
- References No definition available. 
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