Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2019

Share-based Payment Arrangement [Abstract]

Summary of Stock-Based Compensation Expense

Stock-based compensation expense, included within “total operating costs and expenses” for the three and six months ended June 30, 2019 and 2018, was as follows:

	Three Months Ended June 30,				Six Months Ended June 30,
	2019		2018		2019		2018
Selling, general and administrative	$	3,675	$	2,531	$	7,326	$	4,784
Research and development	1,344		650		2,289		1,281
Total stock-based compensation	$	5,019	$	3,181	$	9,615	$	6,065