Quarterly report pursuant to Section 13 or 15(d)

Stock Compensation - Additional Information (Detail)

v3.20.2
Stock Compensation - Additional Information (Detail) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Apr. 17, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Share-based compensation expense $ 29,700 $ 10,700 $ 55,000 $ 30,200  
Non-cash charge related to cancellation of unvested shares     $ 18,200    
Cancellation of unvested shares     750,000    
Stock redeemed, value   $ 161 $ 5,659 $ 13,745  
Unrecognized compensation cost related to unvested common shares $ 66,000   $ 66,000    
Weighted average period for recognition of cost     1 year 9 months 18 days    
Class A Common Stock [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Stock redeemed, shares 171,120 4,821 171,120 423,206  
Stock redeemed, value $ 5,700 $ 200 $ 5,700 $ 13,700  
2017 Plan [Member] | Class A Common Stock [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Number of shares reserved for issuance         15,000,000