Prepaid Expenses and Other Current Assets (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Prepaid Expenses and Other Current Assets
Prepaid development expenses	$ 1,473,402	$ 1,211,668
Prepaid insurance	321,463	282,440
Other	36,093	51,809
Total prepaid expenses and other current assets	$ 1,830,958	$ 1,545,917