Condensed Statements of Changes in Stockholders' Equity (Deficit) - 6 months ended Jun. 30, 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	69,513			$ 34			69,479
Exercise of stock options, shares				33,651
Stock-based compensation expense	1,385,108						1,385,108
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	91,768			$ 40			91,728
Employee stock purchase plan, shares				39,976
Issuance of common stock		$ 556,706	$ 37,724,316		$ 261	$ 13,915		$ 556,445	$ 37,710,401
Issuance of common stock, shares					261,352	13,915,000
MidCap Term Loan warrant discount	74,000						74,000
Net loss	(9,482,676)										(9,482,676)
Other comprehensive loss	(11,339)									$ (11,339)
Balance at Jun. 30, 2018	$ 27,214,616			$ 28,414			$ 171,246,278			$ (11,339)	$ (144,048,737)
Balance, shares at Jun. 30, 2018				28,414,524