Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2022

Share-Based Payment Arrangement [Abstract]

Schedule of non-cash stock-based compensation expense

Non-cash stock-based compensation expense (service-based stock options, restricted stock units and employee stock purchase plan) is summarized in the following table:

	Three Months Ended June 30,				Six Months Ended June 30,
(in thousands)	2022		2021		2022		2021
Cost of product sales	$	1,035	$	1,287	$	2,153	$	2,199
Research and development	1,520		1,234		2,870		2,096
Selling, general and administrative	8,253		8,345		15,316		13,590
Total non-cash stock-based compensation expense	$	10,808	$	10,866	$	20,339	$	17,885