STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock [Member]		Additional paid-in capital [Member]	Receipts on account of shares [Member]	Accumulated Deficit [Member]	Total
Balance at Dec. 31, 2018	$ 11		$ 94,620	$ 4,408	$ (94,023)	$ 5,016
Balance (in shares) at Dec. 31, 2018	20,757,816
Stock-based compensation related to warrants and stock granted to service providers			25			25
Stock-based compensation related to warrants and stock granted to service providers (in shares)	5,908
Stock-based compensation related to stock and options granted to directors and employees			312			312
Stock-based compensation related to stock and options granted to directors and employees (in shares)	39,386
Exercise and reissuance of warrants			3,368	(3,368)
Exercise and reissuance of warrants (in shares)	687,500
Net loss					(5,027)	(5,027)
Balance at Mar. 31, 2019	$ 11	[1]	98,325	1,040	(99,050)	326
Balance (in shares) at Mar. 31, 2019	21,490,610
Balance at Dec. 31, 2018	$ 11		94,620	4,408	(94,023)	5,016
Balance (in shares) at Dec. 31, 2018	20,757,816
Net loss						(15,561)
Balance at Sep. 30, 2019	$ 11		102,796		(109,584)	(6,777)
Balance (in shares) at Sep. 30, 2019	22,605,792
Balance at Mar. 31, 2019	$ 11	[1]	98,325	1,040	(99,050)	326
Balance (in shares) at Mar. 31, 2019	21,490,610
Stock-based compensation related to stock and options granted to directors and employees	$ 0		53		0	53
Stock-based compensation related to stock and options granted to directors and employees (in shares)	0
Exercise and reissuance of warrants			1,040	$ (1,040)
Exercise and reissuance of warrants (in shares)	212,499
Exercise of options			5			5
Exercise of options (in shares)	5,333
Net loss					(4,900)	(4,900)
Balance at Jun. 30, 2019	$ 11		99,423		(103,950)	(4,516)
Balance (in shares) at Jun. 30, 2019	21,708,442
Stock-based compensation related to stock and options granted to directors and employees			217			217
Stock-based compensation related to stock and options granted to directors and employees (in shares)	42,718
Exercise and reissuance of warrants			3,126			3,126
Exercise and reissuance of warrants (in shares)	841,300
Exercise of options			30			30
Exercise of options (in shares)	13,332
Net loss					(5,634)	(5,634)
Balance at Sep. 30, 2019	$ 11		102,796		(109,584)	(6,777)
Balance (in shares) at Sep. 30, 2019	22,605,792
Balance at Dec. 31, 2019	$ 11		105,042		(117,276)	(12,223)
Balance (in shares) at Dec. 31, 2019	23,174,228
Stock-based compensation related to stock and options granted to directors and employees			390		0	390
Stock-based compensation related to stock and options granted to directors and employees (in shares)	54,956
Issuance of shares in at-the-market (ATM) offering (Note 7)	$ 1		18,971			18,972
Issuance of shares in at-the-market (ATM) offering (Note 7) (in shares)	3,935,320
Issuance of shares and warrants in Registered Direct Offering (Note 7)			9,957			9,957
Issuance of shares and warrants in Registered Direct Offering (Note 7) (in shares)	1,250,000
Exercise of options			29		0	29
Exercise of options (in shares)	9,333
Net loss					(8,114)	(8,114)
Balance at Mar. 31, 2020	$ 12		134,389		(125,390)	9,011
Balance (in shares) at Mar. 31, 2020	28,423,837
Balance at Dec. 31, 2019	$ 11		105,042		(117,276)	(12,223)
Balance (in shares) at Dec. 31, 2019	23,174,228
Net loss						(19,996)
Balance at Sep. 30, 2020	$ 12		163,238		(137,272)	25,978
Balance (in shares) at Sep. 30, 2020	31,567,592
Balance at Mar. 31, 2020	$ 12		134,389		(125,390)	9,011
Balance (in shares) at Mar. 31, 2020	28,423,837
Stock-based compensation related to stock and options granted to directors and employees			791			791
Stock-based compensation related to stock and options granted to directors and employees (in shares)	79,491
Issuance of shares in at-the-market (ATM) offering (Note 7)			7,411			7,411
Issuance of shares in at-the-market (ATM) offering (Note 7) (in shares)	1,162,527
Exercise of options			3			3
Exercise of options (in shares)	4,000
Net loss					(7,394)	(7,394)
Balance at Jun. 30, 2020	$ 12		142,594		(132,784)	9,822
Balance (in shares) at Jun. 30, 2020	29,669,855
Stock-based compensation related to stock and options granted to directors and employees			1,017			1,017
Stock-based compensation related to stock and options granted to directors and employees (in shares)	45,797
Issuance of shares in at-the-market (ATM) offering (Note 7)			13,307			13,307
Issuance of shares in at-the-market (ATM) offering (Note 7) (in shares)	947,627
Exercise of options			20			20
Exercise of options (in shares)	4,313
Exercise of warrants			6,300			6,300
Exercise of warrants (in shares)	900,000
Net loss					(4,488)	(4,488)
Balance at Sep. 30, 2020	$ 12		$ 163,238		$ (137,272)	$ 25,978
Balance (in shares) at Sep. 30, 2020	31,567,592

[1] Represents an amount less than $1.