v3.26.1
Reserve for Losses and Loss Adjustment Expenses - Narrative (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Nov. 11, 2024
Jul. 02, 2024
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Dec. 31, 2024
Reserve For Losses And Loss Adjustment Expenses [Line Items]            
Allowance for credit losses on reinsurance recoverables     $ 1,700 $ 1,500 $ 1,600 $ 1,200
Development on prior year loss adverse (favorable) reserves     (165) (131)    
Reduction in pre-tax income     10,635 (16,009)    
Adverse prior year development ceded on subject business     14,189 (1,928)    
Excess & Surplus Lines            
Reserve For Losses And Loss Adjustment Expenses [Line Items]            
Development on prior year loss adverse (favorable) reserves     (100) (10)    
Adverse prior year development ceded on subject business     14,189 (1,928)    
Excess & Surplus Lines | Commercial Auto LPT | Commercial Auto LPT            
Reserve For Losses And Loss Adjustment Expenses [Line Items]            
Cumulative amounts ceded under loss portfolio transfer     451,400   451,400  
Adverse prior year development ceded on subject business     0 144    
Excess & Surplus Lines | E&S ADC            
Reserve For Losses And Loss Adjustment Expenses [Line Items]            
Development on prior year loss adverse (favorable) reserves         35,000  
Reinsure excess amount   $ 716,600        
Reinsurance, aggregate coverage limit $ 1,183,700 467,100        
Payments for reinsurance   $ 313,200        
Adverse prior year development ceded on subject business     0 0    
Excess & Surplus Lines | E&S ADC | State National            
Reserve For Losses And Loss Adjustment Expenses [Line Items]            
Reinsure percentage   85.00%        
Reinsurance, aggregate coverage limit   $ 397,000        
Excess & Surplus Lines | E&S Top Up ADC            
Reserve For Losses And Loss Adjustment Expenses [Line Items]            
Development on prior year loss adverse (favorable) reserves     16,200   51,400  
Reinsure percentage 100.00%          
Reinsurance, aggregate coverage limit $ 75,000          
Payments for reinsurance 52,800          
Reduction in pre-tax income $ 52,800          
Reinsurance, amount remaining     7,500   $ 23,600  
Adverse prior year development ceded on subject business     14,780 0    
Specialty Admitted Insurance            
Reserve For Losses And Loss Adjustment Expenses [Line Items]            
Development on prior year loss adverse (favorable) reserves     $ (65) $ (121)