Stock Based Compensation (Tables)

9 Months Ended

Sep. 30, 2017

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

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs

Stock-based compensation expense before income tax expense for the three and nine-month periods ended September 30, 2017 and 2016, consisted of the following (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2017		2016		2017		2016
Cost of goods sold	$	189	$	105	$	453	$	369
Research and development	110		51		262		147
Selling, general, and administrative	893		347		2,168		1,397
Stock-based compensation expense before taxes	$	1,192	$	503	$	2,883	$	1,913

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

In applying the Black-Scholes methodology to the options granted during the nine-month periods ended September 30, 2017 and 2016, the fair value of our stock-based awards granted was estimated using the following assumptions for the periods indicated below:

	Nine Months Ended September 30,
	2017	2016
Risk-free interest rate	1.77% - 1.83%	1.15% - 1.40%
Expected option life	5.0 years	5.0 years
Expected dividend yield	—%	—%
Expected price volatility	33.81% - 34.07%	36.30% - 37.06%