Stock Compensation (Tables)

9 Months Ended

Sep. 30, 2019

Stock Compensation [Abstract]

Schedule of Share Based Compensation Stock Options Activities

The following table summarizes stock option activity during the nine months ended September 30, 2019:

				Weighted
				Average
	Number	Weighted		Remaining	Aggregate
	of Options	Average		Contractual	Intrinsic Value
	(in thousands)	Exercise Price		Term (years)	(in thousands)
Outstanding at December 31, 2018	1,873	$	97.63	7.5	$	45,381
Granted	484	$	105.55	—	$	—
Exercised	(69)	$	36.59	—	$	—
Cancelled/forfeited	(148)	$	92.40	—	$	—
Expired	(54)	$	165.26	—	$	—
Outstanding at September 30, 2019	2,086	$	97.93	7.4	$	11,747
Expected to vest	985	$	91.42	8.7	$	2,533
Exercisable	1,101	$	103.75	6.3	$	9,214

Schedule of Share Based Compensation Arrangement By Share Based Payment Award Grants in Period Fair Value Assumptions

The Company estimated the fair value of stock options granted in the periods presented utilizing a Black-Scholes option-pricing model utilizing the following assumptions:

	Nine Months Ended September 30,
	2019		2018
Volatility	87.0 - 89.9	%	58.9 - 75.8	%
Expected term (in years)	5.5 - 6.0		6.0
Risk-free rate	1.4 - 2.9	%	1.8 - 2.9	%
Expected dividend yield	—	%	—	%

Schedule of Share-based Compensation, Restricted Stock Units Award Activity

The following table summarizes the aggregate RSU, restricted stock award (“RSA”), PRSU and performance restricted share award (“PRSA”) activity during the nine months ended September 30, 2019:

		Weighted
	Number of	Average Grant Date
	Awards	Fair Value
	(in thousands)
Non-vested awards at December 31, 2018	773	$	76.10
Granted	354	$	110.05
Vested	(261)	$	78.71
Forfeited	(83)	$	85.67
Non-vested awards at September 30, 2019	783	$	89.57

Schedule of Stock Based Compensation Expense

Stock-based compensation expense has been reported in the Company’s condensed consolidated statements of operations as follows:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2019		2018		2019		2018
		(in thousands)			(in thousands)
Selling, general and administrative	$	10,104	$	9,436	$	33,029	$	28,875
Research and development		3,026		2,558		9,780		9,540
Total stock-based compensation	$	13,130	$	11,994	$	42,809	$	38,415