Inventories (Schedule of Inventories) (Details) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Raw materials	$ 131,274,227	$ 139,272,129
Work-in-process	31,221,874	30,481,192
Finished goods	49,879,554	47,012,262
Total Inventory	$ 212,375,655	$ 216,765,583	[1]

[1] The condensed consolidated balance sheet at December 31, 2017 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.3