Inventory (Details) - USD ($) |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Inventory | ||
| Raw materials | $ 3,241,642 | $ 2,025,674 |
| Work in process | 135,626 | 184,478 |
| Finished goods | 716,666 | 286,164 |
| Inventory before allowance for excess and obsolete | 4,093,934 | 2,496,316 |
| Allowance for excess and obsolete | (207,344) | (113,158) |
| Total | $ 3,886,590 | $ 2,383,158 |