Inventories (Schedule of Inventories) (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Raw materials	$ 143,533,414	$ 139,058,541
Work-in-process	35,811,334	35,386,615
Finished goods	45,958,294	50,836,443
Total Inventory	$ 225,303,042	$ 225,281,599	[1]

[1] The condensed consolidated balance sheet at December 31, 2018 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements.