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

Revenue Recognition - Additional Information (Detail)

v3.21.2
Revenue Recognition - Additional Information (Detail) - USD ($)
$ in Millions
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
Deferred revenue, revenue recognized $ 7.1   $ 7.8      
Deferred revenue $ 6.8   $ 6.8   $ 7.8  
Percentage of revenue represented by each customer 28.00% 18.00% 21.00% 16.00%    
Contract With Customer Liability Current         $ 7.8 $ 6.1
Contract with customers liability revenue recognized           $ 6.1
Customer Concentration Risk Member | Sales Revenue Net Member | Maximum [Member]            
Percentage of revenue represented by each customer           10.00%
Major Customer One | Customer Concentration Risk Member | Sales Revenue Net Member            
Percentage of revenue represented by each customer         16.70%  
Major Customer One | Customer Concentration Risk Member | Accounts Receivable Member            
Percentage of revenue represented by each customer         20.10%