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

Business Combination - Additional Information (Detail)

v3.21.2
Business Combination - Additional Information (Detail) - USD ($)
12 Months Ended
Nov. 22, 2019
Dec. 31, 2019
Sep. 30, 2021
Dec. 31, 2020
Dec. 30, 2019
Business Acquisition [Line Items]          
Business acquisition, transaction costs     $ 23,700,000    
Business Combination Consideration Transferred1 $ 44,500,000        
Payments to Acquire Businesses Gross 37,500,000        
Business Combination Consideration Transferred Equity Interests Issued and Issuable 7,000,000        
Goodwill 6,527,000 $ 382,247,000 $ 382,190,000 $ 382,749,000 $ 376,000,000
Minimum [Member]          
Business Acquisition [Line Items]          
Goodwill 400,000        
UBS Bank [Member]          
Business Acquisition [Line Items]          
Line of Credit Facility, Maximum Borrowing Capacity $ 35,000,000.0        
lntegron LLC [Member]          
Business Acquisition [Line Items]          
Percentage of Voting Interests Acquired 100.00%        
Stock Issued During Period Shares Acquisitions 573,016        
Stock Issued During Period, Value, Acquisitions $ 7,000,000.0        
Business acquisition, transaction costs 700        
Business Combination Consideration Transferred1 44,500,000        
Payments to Acquire Businesses Gross 37,500,000        
Business Combination Consideration Transferred Equity Interests Issued and Issuable $ 7,000,000.0        
Business Acquisition Share Price $ 12        
Business Acquisitions pro Forma Revenue   207,000,000.0      
Business Acquisitions pro Forma Net Income Loss   15,900,000      
Business Combination Acquisition Related Costs   $ 700,000      
lntegron LLC [Member] | Minimum [Member]          
Business Acquisition [Line Items]          
Finite Lived Intangible Asset Useful Life 5 years        
lntegron LLC [Member] | Maximum [Member]          
Business Acquisition [Line Items]          
Finite Lived Intangible Asset Useful Life 13 years