Summary of Accrued Liabilities (Details) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Payables And Accruals [Abstract]
Accrued employee bonuses	$ 1,365,489	$ 3,049,109
Payroll and employee benefit accruals	623,713	369,275
Accrued professional fees	112,320	101,150
Accrued interest	107,116	45,544
Other accrued liabilities	219,138	181,708
Total accrued liabilities	$ 2,427,776	$ 3,746,786