Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Stock Options Activity

The following is a summary of stock option activity during the three months ended March 31, 2021:

	Options Outstanding
	Number of Options			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life (years)		Aggregate Intrinsic Value
Balance—January 1, 2021		1,570,728		$	9.09		7.71	$	12,756
Options granted		—		$	—		—	$	—
Options exercised		(978,495	)	$	9.01		—	$	—
Options cancelled		—		$	—		—	$	—
Balance—March 31, 2021		592,233		$	9.22		7.56	$	12,013
Exercisable as of March 31, 2021		370,183		$	9.09		7.48	$	7,556
Vested and expected to vest as of March 31, 2021		592,233		$	9.22		7.56	$	12,013

Summary of Restricted Stock Award Activity

A summary of restricted stock award activity within the Company’s equity plans and changes for the three months ended March 31, 2021 is as follows:

Restricted Stock Awards	Shares			Weighted Average Grant- Date Fair Value
Nonvested at January 1, 2021		3,259,389		$	13.51
Granted		—		$	—
Vested		(542,834	)	$	15.77
Forfeited		—		$	—
Nonvested at March 31, 2021		2,716,555		$	11.81

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 months ended March 31, 2020 and 2021:

	Three Months Ended March 31,
	2020		2021
	(in thousands)
Sales and distribution expenses	$	1,592	$	955
Research and development expenses		1,273		883
General and administrative expenses		4,574		5,061
Total stock-based compensation expense	$	7,439	$	6,899