Net Loss per Common Share - Computation of Basic and Diluted Net Loss per Common Share (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Basic and diluted net loss per common share:
Net loss	$ (7,084,316)	$ (6,812,190)	$ (15,079,355)	$ (12,678,131)
Weighted average common shares outstanding, basic and diluted	23,595,702	19,149,417	21,578,011	19,149,417
Net loss per common share, basic and diluted	$ (0.30)	$ (0.36)	$ (0.70)	$ (0.66)