Stock-based compensation (Tables)

9 Months Ended

Sep. 30, 2018

Share-based Compensation [Abstract]

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

The following table sets forth the stock-based compensation expense recognized in the Consolidated Statements of Income (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2018		2017		2018		2017
Cost of goods sold	$	843	$	788	$	2,313	$	1,820
Research and development	1,967		1,329		5,014		3,805
Selling, general and administrative	7,752		7,774		17,635		19,120
Stock-based compensation expense before income taxes	$	10,562	$	9,891	$	24,962	$	24,745

Stock-based compensation expense capitalized in the Consolidated Balance Sheets is as follows (in thousands):

	September 30,
	2018		2017
Capitalized in inventory	$	1,115	$	1,074