Quarterly report pursuant to Section 13 or 15(d)

Inventories (Details)

v3.19.1
Inventories (Details) - USD ($)
Mar. 31, 2019
Dec. 31, 2018
Inventory Disclosure [Abstract]    
Raw materials $ 58,479,988 $ 59,778,767
Work-in-process 18,095,167 21,033,532
Finished goods 37,582,787 33,389,087
Total inventories $ 114,157,942 $ 114,201,386