STOCK-BASED COMPENSATION (Tables)

3 Months Ended

Mar. 31, 2022

Share-based Payment Arrangement [Abstract]

Summary of Stock-Based Compensation Expense

Total stock-based compensation expense recognized in the Company’s condensed consolidated statements of operations and comprehensive loss is classified as follows (in thousands):

	Three Months Ended March 31,
	2022		2021
Cost of revenue	$	176	$	236
Research and development	724		637
Selling and marketing	693		295
General and administrative	3,439		7,326
Total stock-based compensation expense	$	5,032	$	8,494

Summary of Incentive Stock Units

The table below summarizes the Company’s activity and related information for its ISUs:

	RSUs and DSUs			PSUs
	Number of Shares	Weighted Average Grant Date Fair Value		Number of Shares		Weighted Average Grant Date Fair Value
Unvested at December 31, 2021	5,536,925	$	4.04	707,088		$	4.66
ISUs granted	1,847,172	$	4.21	1,600,549	(1)	$	4.25
ISUs vested	(1,573,992)	$	4.05	—		$	—
ISUs forfeited	(117,372)	$	4.01	(4,756)		$	4.66
Unvested at March 31, 2022	5,692,733	$	4.07	2,302,881		$	4.38
Vested and unreleased	198,856			—
Outstanding at March 31, 2022	5,891,589			2,302,881

(1)     Includes PSUs granted in 2021 assuming a 150% payout.

Summary of Company's Stock Option Activity and Related Information

A summary of the Company’s stock option activity and related information is as follows:

	Number of Stock Options Outstanding	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
					(In thousands)
Options outstanding at December 31, 2021	7,156,776	$	6.97	6.1	$	5,203
Options granted	—	—
Options exercised	(19,292)	$	2.91
Options cancelled or forfeited	(133,995)	$	8.18
Options outstanding at March 31, 2022	7,003,489	$	6.96	5.9	$	2,651
Options exercisable at March 31, 2022	6,117,485	$	7.06	5.7	$	2,038
Options vested and expected to vest at March 31, 2022	6,938,310	$	6.99	5.8	$	2,560