General form of registration statement for all companies including face-amount certificate companies

Share-Based Payment and Related Stock Option Plan - Additional Information (Detail)

v3.21.2
Share-Based Payment and Related Stock Option Plan - Additional Information (Detail) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2021
Sep. 30, 2020
Sep. 30, 2021
Sep. 30, 2020
Dec. 31, 2020
Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Share-based payment arrangement, expense $ 3,933 $ 315 $ 4,564 $ 846 $ 1,161 $ 1,682
Share-based payment arrangement, non vested award, cost not yet recognized, amount $ 0   0   3,416 3,793
Fair value of options vested         2,500 1,300
aggregate intrinsic value of options outstanding         8,900  
intrinsic value of options exercisable         2,600  
total intrinsic value of options exercised         0 $ 0
Cancellation Agreements [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Payment of Option Cash Consideration     $ 4,075,000   $ 4,075,000  
Cancellation Agreements [Member] | Common Stock [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Stock Issued During Period, Shares, New Issues     432,500   432,500  
Stock issued during the period value new issues     $ 3,377,825   $ 4,325,000