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Municipal Bond Guarantee Reinsurance - Schedule of Municipal Bond Guarantee Insured Obligations (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 USD ($) contract | Dec. 31, 2023 USD ($) 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 | 15,884 | 14,485
Remaining weighted average contract period(in years) | 11 years 2 months 12 days | 11 years 1 month 6 days
Outstanding par value of policies assumed (in millions) | $ 18,503.3 | $ 16,575.2
Gross unearned insurance premiums (in millions) | $ 297.3 | 273.9
HG/BAM |  |
Guarantor Obligations [Line Items] |  |
Outstanding par value of policies assumed (in millions) |  | 109,673.8
Gross unearned insurance premiums (in millions) |  | 325.8
Total debt service outstanding |  | 165,686.0
Interest |  | $ 56,012.2

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