Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2014

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Assumptions used in the Black-Scholes Option-Pricing Model

The assumptions used in the Black-Scholes option-pricing model for the three and nine months ended September 30, 2014 and 2013 are as follows:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2014		2013		2014	2013
Risk free interest rate	2.0%		1.5% to 1.7%		1.6% to 2.0%	0.8% to 1.7%
Expected term	6.1 years		5.1 to 6.0 years		5.1 to 6.1 years	5.0 to 6.1 years
Expected volatility	83.8%		82.8% to 83.9%		83.8% to 84.9%	82.8% to 87.9%
Expected dividend yield	—	%	—	%	—%	—%

Stock-Based Compensation Expense

The Company recognized stock-based compensation expense as follows (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2014		2013		2014		2013
Cost of goods sold	$	101	$	119	$	369	$	227
Research and development	262		316		983		782
Selling, general and administrative	1,679		1,780		5,982		4,570
Restructuring	—		—		—		201
Total	$	2,042	$	2,215	$	7,334	$	5,780