Annual report pursuant to Section 13 and 15(d)

Employee Benefit Plan - Additional Information (Detail)

v3.20.4
Employee Benefit Plan - Additional Information (Detail) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Payment Arrangement [Abstract]      
Employer contribution as a percentage of employee contributions 2.00%    
Employer contribution 25.00%    
Full vesting period of employer contribution 4 years    
Contribution expenses $ 11.9 $ 12.2 $ 10.1