Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2022

Stock-Based Compensation [Abstract]

Classification of Stock-Based Compensation Expense

The following table presents the classification of stock-based compensation expense recognized for the periods below:

	Three months ended September 30,				Nine months ended September 30,
(in thousands)	2022		2021		2022		2021
Selling, general and administrative expense	$	199	$	216	$	624	$	894
Research and development expense		21		40		73		99
Total stock-based compensation expense	$	220	$	256	$	697	$	993