Stock-Based Compensation (Details 1) - Employee Stock Option	9 Months Ended
	Sep. 30, 2018 $ / shares shares
Number of Options
Number of options outstanding, balance beginning (in shares) | shares	4,299,810
Number of options issued (in shares) | shares	735,785
Number of options exercised (in shares) | shares	(236,000)
Number of options forfeited (in shares) | shares	(404,251)
Number of options expired (in shares) | shares	0
Number of options outstanding, balance ending (in shares) | shares	4,395,344
Number of options exercisable (in shares) | shares	3,247,214
Weighted Average Exercise Price
Shares outstanding exercise price, balance beginning (in dollars per share) | $ / shares	$ 5.09
Issued, exercise price (in dollars per share) | $ / shares	3.35
Exercised, exercise price (in dollars per share) | $ / shares	1.04
Forfeited, exercise price (in dollars per share) | $ / shares	7.71
Expired, exercise price (in dollars per share) | $ / shares	0
Shares outstanding exercise price, balance ending (in dollars per share) | $ / shares	4.78
Exercisable, exercise price (in dollars per share) | $ / shares	$ 4.74