Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Accrued Liabilities, Current [Abstract]
Accrued compensation expenses	$ 1,553,276	$ 1,832,630
Accrued professional services	85,997	76,224
Accrued royalties	58,795	119,630
Accrued other	1,003,947	871,645
Total	$ 2,702,015	$ 2,900,129