STATEMENTS OF CHANGES IN PREFERRED STOCK AND STOCKHOLDERS' Equity (DEFICIT) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Issuance of common stock, commissions and expenses		$ 2,898	$ 2,700
Common stock issuance cost		$ 2,898	$ 2,700
Market Offering [Member]
Issuance of common stock, commissions and expenses	$ 100
Common stock issuance cost	100
Warrant [Member]
Issuance of common stock, commissions and expenses	1,100
Common stock issuance cost	$ 1,100