Condensed Consolidated Statements of Stockholders' Equity (Deficit) (Unaudited) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]	Total
Balances at Dec. 31, 2019	$ 22	$ 270,555	$ (284,895)	$ (14,318)
Balances (in shares) at Dec. 31, 2019	22,806,890
Issuance of common stock, net of expenses		65		65
Issuance of common stock, net of expenses, shares	40,000
Issuance of common stock in exchange for services		13		13
Issuance of common stock in exchange for services, shares	5,868
Issuance of stock options for payment of compensation		133		133
Issuance of stock options for payment of compensation, shares
Issuance of common stock for payment of compensation		19		19
Issuance of common stock for payment of compensation, shares	9,599
Issuance of warrant for services		1		1
Stock-based compensation expense		265		265
Net loss			(2,467)	(2,467)
Balances at Mar. 31, 2020	$ 22	271,051	(287,362)	(16,289)
Balances (in shares) at Mar. 31, 2020	22,862,357
Balances at Dec. 31, 2020	$ 52	419,923	(374,430)	45,545
Balances (in shares) at Dec. 31, 2020	51,626,508
Issuance of common stock, net of expenses	$ 2	36,104		36,106
Issuance of common stock, net of expenses, shares	1,796,858
Issuance of common stock upon option exercise		429		429
Issuance of common stock upon option exercise, shares	233,323
Stock-based compensation expense		510		510
Net loss			(65,567)	(65,567)
Balances at Mar. 31, 2021	$ 54	$ 456,966	$ (439,997)	$ 17,023
Balances (in shares) at Mar. 31, 2021	53,656,689