Stock-Based Compensation (Tables)

3 Months Ended

12 Months Ended

Mar. 31, 2022

Dec. 31, 2021

Schedule Of Stock Based Compensation Expense [Abstract]

Schedule of Weighted Average Grant Fair Value of Stock Options using Black-Scholes Option-pricing Model

The following table presents, on a weighted average basis, the assumptions used in the Black-Scholes option-pricing model to determine the grant-date fair value of stock options granted during the three months ended March 31, 2022:

Risk-free interest rate	1.8	%
Expected term (in years)	6.0
Expected volatility	76.5	%
Expected dividend yield	0	%

The following table presents, on a weighted average basis, the assumptions used in the Black-Scholes option-pricing model to determine the grant-date fair value of stock options granted during the years ended December 31, 2021 and 2020:

	Year Ended December 31,
	2021			2020
Risk-free interest rate		0.8	%		1.0	%
Expected term (in years)		4.65			6.0
Expected volatility		80.4	%		67.8	%
Expected dividend yield		—	%		—	%

Schedule of Stock Option Activity

The following table summarizes option activity with service conditions under the 2021 Plan and the 2017 Plan:

	Options			Weighted average exercise price		Weighted average contract life		Aggregate Intrinsic Value
Balance at January 1, 2022		24,064,586		$	4.23		7.4	$	56,525
Granted		120,727		$	5.08
Exercised		(10,255	)	$	3.74
Forfeited		(175,852	)	$	6.89
Outstanding at March 31, 2022		23,999,206		$	4.22		8.59	$	117,847
Vested and expected to vest March 31, 2022		23,999,206		$	4.22		8.59	$	117,847
Exercisable at March 31, 2022		20,203,497		$	3.55		8.55	$	111,059

The following table summarizes option activity under the 2021 Plan and the 2017 Plan:

	Options			Weighted average exercise price		Weighted average contract life		Aggregate Intrinsic Value
Balance at December 31, 2019		13,954,174		$	0.75		7.6	$	40,572
Granted		4,662,072			3.70
Exercised		(108,369	)		3.88
Forfeited		(1,340,712	)		2.17
Outstanding at December 31, 2020		17,167,165		$	1.63		7.3	$	100,633
Granted		9,681,736			8.57
Exercised		(703,512	)		0.91
Forfeited		(2,080,803	)		4.04
Outstanding at December 31, 2021		24,064,586		$	4.23		7.4	$	56,525
Vested and expected to vest December 31, 2021		24,064,586		$	4.23		7.4	$	56,525
Exercisable at December 31, 2021		17,840,068		$	3.51		6.9	$	51,898

Schedule of Activity Related to RSU Stock-Based Payment Awards

The following table summarizes activity related to RSU stock-based payment awards:

	Number Shares			Weighted average grant date fair value
Outstanding at December 31, 2021		474,700		$	7.20
Granted		54,466		$	4.59
Forfeited		(11,550	)	$	7.20
Outstanding at March 31, 2022		517,616		$	6.93

The following table summarizes activity related to RSU stock-based payment awards: 

	Number of shares			Weighted average grant date fair value
Outstanding at December 31, 2020		—		$	—
Granted		488,600			7.20
Forfeited		(13,900	)		7.20
Outstanding at December 31, 2021		474,700		$	7.20

Schedule of Stock-based Compensation Expense

The Company recorded stock-based compensation expense in the following expense categories of its condensed consolidated statements of operations:

	Three Months Ended March 31,
	2022		2021
Cost of revenue	$	37	$	16
Research and development		248		347
Selling, general and administrative		2,137		646
	$	2,422	$	1,009

The company recorded stock-based compensation expense in the following expense categories of its consolidated statements of operations:

	Year Ended December 31,
	2021		2020
Cost of goods sold	$	72	$	70
Research and development		11,105		1,384
Selling, general and administrative		28,833		2,917
	$	40,010	$	4,371