Share-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2018

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Schedule of Weighted Average Assumptions Used in Black -Scholes Valuation Model

The following table presents the weighted-average assumptions used in the Black-Scholes valuation model by the Company in calculating the fair value of share options granted:

	For the Three Months Ended September 30,						For the Nine Months Ended September 30,
	2018			2017			2018			2017
Expected life (in years)		6.1			7.6			6.1			7.3
Expected volatility		73.3	%		76.1	%		73.3	%		76.4	%
Expected dividend yield		—	%		—	%		—	%		—	%
Risk-free interest rate		2.76	%		1.83	%		2.76	%		1.87	%
Grant date weighted average fair value	$	5.61		$	9.57		$	5.61		$	7.94

Summary of Share Option Activity

The following table summarizes the Company’s share option activity for all plans for the nine months ended September 30, 2018:

	Number of Shares			Weighted Average Exercise Price		Weighted- Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value (in thousands)
Outstanding - December 31, 2017		344,055		$	8.70
Granted		926,931		8.47
Exercised		(62,224	)	5.34
Forfeited/cancelled		(130,579	)	17.45
Outstanding - September 30, 2018		1,078,183		$	7.64	9.29		1,386
Exercisable - September 30, 2018		168,360		$	3.95	6.57		832
Exercisable and expected to vest - September 30, 2018		1,078,183		$	7.64	9.29		1,386