v3.26.1
Stock-Based Compensation (Exzeo Plan) - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Common shares available for grant 644,994    
Stock options, outstanding 570,000   590,000
Exercisable, Number of Options 570,000    
Recognized compensation expenses $ 3,359 $ 2,972  
Restricted Stock      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Restricted stock awards outstanding, nonvested 492,192   494,635
Weighted average grant date fair value $ 73.26   $ 73.31
Unrecognized compensation expense related to nonvested stock awards $ 18,156    
Recognition of remaining compensation expense over a weighted-average period 2 years 3 months 18 days    
Exzeo Group Inc | Share based Awards      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Common shares available for grant 9,776,820    
Exzeo Group Inc | Employee Stock Option      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock options, outstanding 6,350,000    
Weighted-average exercise price $ 23    
Exzeo Group Inc | Restricted Stock      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Restricted stock awards outstanding, nonvested 2,533,303    
Weighted average grant date fair value $ 4.74    
Unrecognized compensation expense related to nonvested stock awards $ 11,111    
Recognition of remaining compensation expense over a weighted-average period 4 years    
Exzeo Group Inc | Board Approval Required | Employee Stock Option      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Exercisable, Number of Options 6,000,000    
Exzeo Group Inc | 2021 Equity Incentive Plan [Member] | Share based Awards      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
No of shares authorized 10,000,000