Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-In Capital	Accumulated Deficit	Total
Beginning balance, shares at Dec. 31, 2018	342,578
Beginning balance, value at Dec. 31, 2018		$ 99,489	$ (85,911)	$ 13,578
Issuance of common stock upon the exercise of warrants, shares	130,338
Issuance of common stock upon the exercise of warrants, value		72		72
Issuance of common stock under Lincoln Park Capital, LLC purchase agreement, shares	9,090
Issuance of common stock under Lincoln Park Capital, LLC purchase agreement, value		(58)		(58)
Issuance of restricted stock, shares	4,419
Issuance of restricted stock, value
Issuance of common stock under the employee stock purchase plan, shares	36
Issuance of common stock under the employee stock purchase plan, value		1		1
Issuance of common stock in connection with registered direct public offering, net of offering costs of $234, shares	181,818
Issuance of common stock in connection with registered direct public offering, net of offering costs of $234, value	$ 1	765		766
Issuance of common stock upon vesting of restricted stock units, shares	1,154
Issuance of common stock upon vesting of restricted stock units, value		(3)		(3)
Stock-based compensation expense		300		300
Net Loss			(8,908)	(8,908)
Ending balance, shares at Dec. 31, 2019	669,433
Ending balance, value at Dec. 31, 2019	$ 1	100,566	(94,819)	5,748
Issuance of common stock upon the exercise of warrants, shares	2,205,663
Issuance of common stock upon the exercise of warrants, value		3,856		3,856
Cash in lieu of fractional shares for 1:55 reverse stock split, shares	(1,364)
Cash in lieu of fractional shares for 1:55 reverse stock split, value		(15)		(15)
Issuance of common stock under the employee stock purchase plan, shares	153
Issuance of common stock under the employee stock purchase plan, value		1		1
Issuance of common stock and warrants in connection with registered direct and private placement offerings, net of offering costs of $746, shares	1,910,120
Issuance of common stock and warrants in connection with registered direct and private placement offerings, net of offering costs of $746, value		4,994		4,994
Issuance of common stock, pre-funded warrants and warrants in connection with underwritten public offering, net of offering costs of $906, shares	993,633
Issuance of common stock, pre-funded warrants and warrants in connection with underwritten public offering, net of offering costs of $906, value		7,093		7,093
Issuance of common stock upon vesting of restricted stock units, shares	3,335
Issuance of common stock upon vesting of restricted stock units, value		(2)		(2)
Stock-based compensation expense		136		136
Net Loss			(8,794)	(8,794)
Ending balance, shares at Dec. 31, 2020	5,780,973
Ending balance, value at Dec. 31, 2020	$ 1	$ 116,629	$ (103,613)	$ 13,017