Loan and Security Agreement - Warrants Issued (Details) - USD ($)	1 Months Ended	12 Months Ended
	Nov. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Nov. 09, 2016	Dec. 31, 2014
Exercise price of warrants (in dollars per share)		$ 5.21	$ 3.06	$ 2.02		$ 1.30
Proceeds from Issuance of Long-term Debt			$ 10,000,000
Amortization of debt (premium) discount		$ 470,521	68,930	$ 42,202
Term Loan
Common stock to be issued if warrants are exercised (in shares)	65,228				65,228
Exercise price of warrants (in dollars per share)	$ 7.41				$ 7.41
Term of warrants (in years)	7 years
Proceeds from Issuance of Long-term Debt	$ 10,000,000
Amortization of debt (premium) discount		$ 123,543	$ 19,149