Condensed Statements of Changes in Stockholders' Equity (Deficit) - 3 months ended Mar. 31, 2018 - USD ($)	Total	ATM Offering	Underwritten Public Offering	Common Stock	Common Stock ATM Offering	Common Stock Underwritten Public Offering	Additional Paid-In Capital	Additional Paid-In Capital ATM Offering	Additional Paid-In Capital Underwritten Public Offering	Accumulated Other Comprehensive Loss	Accumulated Deficit
Balance at Dec. 31, 2017	$ (3,059,537)			$ 13,929			$ 131,492,595				$ (134,566,061)
Balance, shares at Dec. 31, 2017				13,929,763
Exercise of stock options	40,504			$ 18			40,486
Exercise of stock options, shares				18,028
Stock-based compensation expense	1,143,188						1,143,188
Vesting of restricted stock awards	270			$ 270
Vesting of restricted stock awards, shares				269,551
Net share settlement of restricted stock award	(133,513)			$ (35)			(133,478)
Net share settlement of restricted stock award, shares				(34,769)
Employee stock purchase plan	$ 14,453						14,453
Issuance of common stock		$ 556,706	$ 37,724,316		$ 262	$ 13,915		$ 556,444	$ 37,710,401
Issuance of common stock, shares	5,733,314			300,000	261,352	13,915,000
MidCap Term Loan warrant discount	$ 74,000						74,000
Net loss	(5,379,947)										(5,379,947)
Other comprehensive loss	(11,151)									$ (11,151)
Balance at Mar. 31, 2018	$ 30,969,289			$ 28,359			$ 170,898,089			$ (11,151)	$ (139,946,008)
Balance, shares at Mar. 31, 2018				28,358,925