Stockholders' Equity (Schedule of Fair Value of Warrants) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Jun. 26, 2019
Class of Warrant or Right [Line Items]
Warrants liability	$ 2,831	$ 7,725	$ 10,798
Series A Warrants
Class of Warrant or Right [Line Items]
Warrants liability			3,862
Series B-1 Warrants
Class of Warrant or Right [Line Items]
Warrants liability			328
Series B-2 Warrant
Class of Warrant or Right [Line Items]
Warrants liability			376
Series C Warrants
Class of Warrant or Right [Line Items]
Warrants liability			$ 6,232