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

Income Tax (Details)

v3.21.2
Income Tax (Details) - 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
Dec. 31, 2018
Aug. 31, 2021
Income Tax [Line Items]                
Income tax provision $ 3,270 $ (1,376) $ 8,361 $ 1,975 $ (3,144) $ 12,053 $ (1,197)  
Effective tax rate 29.20% 31.10% 89.30% 13.80% (18.20%) 34.10% (60.40%)  
Annualized effective tax benefit $ 3,300   $ 2,700          
Annualized effective tax rate 29.20%   29.10%          
Effective income tax reconciliation, state taxes $ 0   $ 5,600          
Effective income tax reconciliation, state taxes (as a percent) 0.00%   60.20%   (7.50%) 11.10% (45.50%)  
Deferred tax asset         $ 8,424 $ 7,370    
Meetrics GmbH                
Income Tax [Line Items]                
Deferred tax liability               $ 2,886
Net operating loss carryforwards         5,000      
Deferred tax asset         $ 1,500