Shareholders' Equity (Details) - Employee Stock Option [Member] $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares shares
Summary of employees and directors share option activity
Number of RSUs, Outstanding, Beginning balance | shares	6,474,982
Number of options, Granted | shares	2,760,500
Number of options, Exercised | shares	(470,899)
Number of options, Expired and forfeited | shares	(1,464,916)
Number of RSUs, Outstanding, Ending balance | shares	7,299,667
Number of options, Options vested and expected to vest | shares	6,989,631
Number of options, Exercisable | shares	3,797,668
Weighted average exercise price, Beginning balance	$ 2.28
Weighted average exercise price, Granted	1.90
Weighted average exercise price, Exercised	1.58
Weighted average exercise price, Expired and forfeited	2.59
Weighted average exercise price, Ending balance	2.12
Weighted average exercise price, Options vested and expected to vest	2.17
Weighted average exercise price, Exercisable options	2.27
Weighted average fair value of options, Granted	$ 0.72
Weighted average remaining contractual term (years), Outstanding, Beginning balance	3 years 4 months 20 days
Weighted average remaining contractual term (years), Outstanding, Ending balance	3 years 9 months 22 days
Weighted average remaining contractual term (years), Options vested and expected to vest	3 years 8 months 26 days
Weighted average remaining contractual term (years), Exercisable options	2 years 5 months 23 days
Aggregate intrinsic value, Outstanding , Beginning balance | $	$ 4,475
Aggregate intrinsic value, Outstanding, Ending balance | $