Stock Based Compensation (Tables)

6 Months Ended

Jun. 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 six-month periods ended June 30, 2017 and 2016, consisted of the following (in thousands):

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Cost of goods sold	$	168	$	141	$	264	$	264
Research and development	100		54		152		96
Selling, general, and administrative	846		591		1,275		1,050
Stock-based compensation expense before taxes	$	1,114	$	786	$	1,691	$	1,410

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

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

	Six months ended June 30,
	2017	2016
Risk-free interest rate	1.77% - 1.79%	1.25% - 1.40%
Expected option life	5.0 years	5.0 years
Expected dividend yield	—%	—%
Expected price volatility	33.81% - 34.03%	36.50% - 37.06%