Municipal Bond Guarantee Reinsurance - Schedule of Municipal Bond Guarantee Insured Obligations (Details) $ in Millions |
9 Months Ended | 12 Months Ended |
|---|---|---|
|
Sep. 30, 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 | 18,495 | 17,377 |
| Remaining weighted average contract period (in years) | 11 years 9 months 18 days | 11 years 7 months 6 days |
| Outstanding par value of policies assumed (in millions) | $ 21,923.0 | $ 20,559.9 |
| Gross unearned insurance premiums (in millions) | $ 342.5 | $ 327.9 |