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

Share-Based Compensation (Details)

v3.21.4
Share-Based Compensation (Details) - USD ($)
$ in Millions
Sep. 30, 2021
Dec. 31, 2020
Sep. 30, 2020
Apr. 16, 2020
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of shares authorized 1,045,000 1,550,000 1,550,000 6,845,297 2,500,000 2,475,000  
Awards outstanding 60,000 950,000     1,125,000 500,000  
Performance hurdle value $ 500       $ 294    
Minimum              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Performance hurdle value   $ 294       $ 120  
Maximum              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Performance hurdle value   $ 900       $ 300  
Equity Incentive Plan              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of shares authorized             6,845,297