Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2020

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Stock Options Activity

The following is a summary of stock option activity during the nine months ended September 30, 2020:

	Options Outstanding
	Number of Options			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life (years)		Aggregate Intrinsic Value
Balance—January 1, 2020		1,862,569		$	9.09		8.64	$	99
Options granted		—		$	—		—	$	—
Options exercised		(2,870	)	$	4.14		—	$	—
Options cancelled		(276,420	)	$	9.28		—	$	—
Balance—September 30, 2020		1,583,279		$	9.07		7.95	$	588
Exercisable as of September 30, 2020		1,062,960		$	8.90		7.84	$	508
Vested and expected to vest as of September 30, 2020		1,583,279		$	9.07		7.95	$	588

Summary of Restricted Stock Award Activity

A summary of restricted stock award activity within the Company’s equity plans and changes for the nine months ended September 30, 2020 is as follows:

Restricted Stock Awards	Shares			Weighted Average Grant- Date Fair Value
Nonvested at January 1, 2020		2,601,972		$	18.21
Granted		691,709		$	3.82
Vested		(416,953	)	$	14.38
Forfeited		(519,695	)	$	17.56
Nonvested at September 30, 2020		2,357,033		$	14.95

Summary of Total Stock-based Compensation Expense by Function

The following table summarizes the total stock-based compensation expense by function, including expense related to consultants, for the three and nine months ended September 30, 2020 and 2019:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2019		2020		2019		2020
	(in thousands)				(in thousands)
Sales and distribution expenses	$	2,421	$	748	$	5,218	$	1,761
Research and development expenses		1,920		778		3,952		3,231
General and administrative expenses		7,033		3,335		15,577		12,480
Total stock-based compensation expense	$	11,374	$	4,861	$	24,747	$	17,472