Share-Based Compensation (Details 3) - $ / shares	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of stock options exercised	156,012	15,217
Weighted average exercise price	$ 1.97	$ 4.80

Number of share options (or share units) exercised during the current period.

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Balance Type:	na
Period Type:	duration