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

Debt and Other Financing - Schedule of Debt Instrument Carrying Amount (Detail)

v3.21.2
Debt and Other Financing - Schedule of Debt Instrument Carrying Amount (Detail) - USD ($)
$ in Thousands
Sep. 30, 2021
Dec. 31, 2020
Dec. 31, 2019
Debt Instrument [Line Items]      
Long-term Debt, Gross $ 81,237 $ 103,435 $ 123,044
Related Party Loans [Member]      
Debt Instrument [Line Items]      
Long-term Debt, Gross $ 81,237 $ 83,737 80,946
Related Party Loans [Member] | Maximum [Member]      
Debt Instrument [Line Items]      
Debt Instrument, Interest Rate, Effective Percentage 6.00% 6.00%  
Related Party Loans [Member] | Minimum [Member]      
Debt Instrument [Line Items]      
Debt Instrument, Interest Rate, Effective Percentage 4.00% 4.00%  
Paycheck Protection Program Loan [Member]      
Debt Instrument [Line Items]      
Long-term Debt, Gross $ 0 $ 3,600  
Debt Instrument, Interest Rate, Effective Percentage 1.86% 1.86%  
Line of Credit [Member]      
Debt Instrument [Line Items]      
Long-term Debt, Gross $ 0 $ 16,098 16,098
Debt Instrument, Interest Rate, Effective Percentage 3.65% 3.65%  
Secured Debt [Member]      
Debt Instrument [Line Items]      
Long-term Debt, Gross     $ 26,000