Income Taxes - Difference in Actual Income Tax Expense Computed by Applying the Statutory Federal Income Tax Rate to Loss Before Income Taxes (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Line Items]
Computed tax (benefit) at 34%	$ (8,850,007)	$ (7,271,785)
State taxes, net of federal benefit	(462,609)	(918,079)
Stock-based compensation	210,367	102,699
Expiring state net operating loss ("NOL") carryforwards	94,962	(20,086)
Return to provision	248,263	(27,934)
Other	25,718	44,679
Change in valuation reserve	9,538,280	8,743,589
Total income tax expense	10,118	10,189
State
Income Tax Disclosure [Line Items]
Research and development tax credit	(453,071)	(300,213)
Federal
Income Tax Disclosure [Line Items]
Research and development tax credit	$ (341,785)	$ (342,681)