Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Net operating loss carryforwards	$ 33,431,082	$ 29,475,597
Research and development credits	3,076,441	3,114,091
Deferred revenue	86,567	204,061
Inventory reserve	9,645	15,134
Fixed assets and intangibles	223,767	147,395
Accrued liability	86,034	24,500
Other	106,913	74,986
Total deferred tax assets	38,740,784	35,008,331
Valuation allowance	(38,740,784)	(35,008,331)
NuvoGen
Deferred tax assets:
Accrued liability	$ 1,720,335	$ 1,952,567