Annual report pursuant to Section 13 and 15(d)

Property, Plant and Equipment (Details)

v3.19.1
Property, Plant and Equipment (Details) - USD ($)
 12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Property, Plant and Equipment [Line Items]      
Total property, plant and equipment, gross $ 98,212,688 $ 85,531,445  
Less accumulated depreciation 57,288,233 50,451,436  
Property, plant and equipment, net 40,924,455 35,080,009  
Depreciation expense 6,411,900 5,294,695 $ 4,235,203
Accumulated depreciation for assets acquired under capital leases 707,112 86,357  
Land      
Property, Plant and Equipment [Line Items]      
Total property, plant and equipment, gross 62,916 62,916  
Leasehold improvements      
Property, Plant and Equipment [Line Items]      
Total property, plant and equipment, gross 1,162,942 544,186  
Buildings      
Property, Plant and Equipment [Line Items]      
Total property, plant and equipment, gross 412,301 412,301  
Machinery, fixtures and equipment      
Property, Plant and Equipment [Line Items]      
Total property, plant and equipment, gross 91,514,620 81,229,311  
Machinery and equipment under capital lease      
Property, Plant and Equipment [Line Items]      
Total property, plant and equipment, gross 1,416,114 401,077  
Construction-in-progress      
Property, Plant and Equipment [Line Items]      
Total property, plant and equipment, gross $ 3,643,795 $ 2,881,654