Quarterly report pursuant to Section 13 or 15(d)

Equity Based Awards - Summary of Stock Option Activity (Detail)

v3.21.2
Equity Based Awards - Summary of Stock Option Activity (Detail) - 2013 Stock Plan [Member]
9 Months Ended 12 Months Ended
Sep. 30, 2021
$ / shares
shares
Dec. 31, 2020
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Number of Shares, Outstanding | shares 18,493,013  
Granted | shares 0  
Exercised | shares (1,827,502)  
Forfeited | shares (286,059)  
Number of Shares, Outstanding | shares 16,379,452 18,493,013
Number of Shares, Options exercisable | shares 5,050,374  
Weighted-Average Exercise Price, Outstanding | $ / shares $ 1.81  
Granted | $ / shares 0.00  
Exercised | $ / shares 0.96  
Forfeited | $ / shares 1.56  
Weighted-Average Exercise Price, Outstanding | $ / shares 1.91 $ 1.81
Weighted-Average Exercise Price, Options exercisable | $ / shares $ 1.46  
Weighted-Average Remaining Contractual Life, Outstanding 8 years 2 months 1 day 8 years 8 months 15 days
Weighted-Average Remaining Contractual Life, exercisable 7 years 3 days