v3.26.1
Municipal Bond Guarantee Insurance - Schedule of Municipal Bond Guarantee Insured Obligations (Details)
$ in Millions
3 Months Ended 12 Months Ended
Mar. 31, 2026
USD ($)
contract
Dec. 31, 2025
USD ($)
contract
Subsidiary - HG Global | Maximum    
Guarantor Obligations [Line Items]    
Percentage of par value of policy reinsured 15.00%  
HG Global    
Guarantor Obligations [Line Items]    
Contracts outstanding | contract 17,721 17,377
Remaining weighted average contract period (in years) 11 years 7 months 6 days 11 years 7 months 6 days
Outstanding par value of policies assumed (in millions) $ 20,856.3 $ 20,559.9
Gross unearned insurance premiums (in millions) $ 328.5 $ 327.9