Stock-Based Compensation Expense (Tables)

3 Months Ended

Mar. 31, 2020

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

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

	Three Months Ended
	March 31,
	2020		2019
Cost of sales	$	339	$	252
Research and development		285		192
Selling, general and administrative		2,153		1,322
Stock-based compensation expense before taxes	$	2,777	$	1,766

Stock Options

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

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

	Three Months Ended
	March 31,
	2020	2019
Risk-free interest rate	0.52% - 1.67%	2.42% - 2.56%
Expected option term	4.0 - 5.0 years	3.0 - 5.0 years
Expected dividend yield	—	—
Expected price volatility	38.65% - 43.24%	28.93% - 33.69%

Stock-Settled Performance-Based Restricted Stock Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

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

	Three Months Ended
	March 31,
	2020
Risk-free interest rate	1.1% - 1.3%
Performance period	0.8 - 2.8 years
Expected dividend yield	—
Expected price volatility	40.2% - 56.1%