Equity-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Summary of Option-Pricing Formula

We account for forfeitures as they occur and apply the following assumptions in our Black-Scholes-Merton Model option-pricing formula:

	Year Ended December 31, 2021	Year Ended December 31, 2020	Year Ended December 31, 2019
Expected term (in years)	3.75 - 10.0	4.0 - 10.0	3.0 - 10.0
Risk-free interest rate	0.34% - 1.34%	0.16% - 1.41%	1.35% - 2.63%
Expected volatility	58% - 78.94%	56% - 76%	54% - 63%
Expected dividend yield	0%	0%	0%

Summary of Option Activity

A summary of option activity under our stock option plans as of December 31, 2021, and the changes during the year is presented below: 

Options	Number of options	Weighted average exercise price		Weighted average remaining contractual term (years)	Aggregate intrinsic value (in thousands)
Outstanding at December 31, 2020	38,587,921	$	6.45	6.78	$	26,054
Granted	12,736,376	$	4.36
Exercised	(445,437)	$	2.43
Forfeited	(2,592,195)	$	3.53
Expired	(819,523)	$	8.98
Outstanding at December 31, 2021	47,467,142	$	6.04	6.58	$	42,807
Vested and expected to vest at December 31, 2021	47,467,142	$	6.04	6.58	$	42,807
Exercisable at December 31, 2021	26,466,365	$	8.00	4.91	$	16,725