Stock-based compensation (Tables)

6 Months Ended

Jun. 30, 2019

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 June 30,				Six Months Ended June 30,
	2019		2018		2019		2018
Cost of goods sold	$	709	$	775	$	1,556	$	1,470
Research and development	1,951		1,638		3,631		3,047
Selling, general and administrative	6,528		6,056		12,091		9,883
Stock-based compensation expense before income taxes	$	9,188	$	8,469	$	17,278	$	14,400

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

	June 30,
	2019		2018
Capitalized in inventory	$	1,016	$	1,068