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v3.25.1

Municipal Bond Guarantee Insurance - Narrative (Details) | 3 Months Ended |  |  |
--- | --- | --- | --- | ---
Mar. 31, 2025 USD ($) | Mar. 31, 2024 USD ($) | Dec. 31, 2024 USD ($) | Jul. 01, 2024 USD ($) | Jun. 30, 2024
Guarantor Obligations [Line Items] |  |  |  |  |
Member surplus contributions, insurance premium charges, percentage | 55.00% |  |  |  |
Direct | $ 6,700,000 | $ 10,500,000 |  |  |
Gross earned premiums | 8,200,000 | 7,800,000 |  |  |
Assets held-in-trust | 976,200,000 |  | $ 950,100,000 |  |
Collateral trusts, investments and cash | 296,700,000 |  | 289,400,000 |  |
Surplus notes | 300,900,000 |  | 300,900,000 |  |
Interest receivable | 15,200,000 |  | 7,700,000 |  |
Debt | 676,100,000 |  | 562,500,000 |  |
Interest income from BAM Surplus Notes | 7,500,000 | 0 |  |  |
Operating Segments | Financial Guarantee (HG Global) |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |
Debt | 147,500,000 |  | 147,400,000 |  |
Interest income from BAM Surplus Notes | 7,500,000 | 0 |  |  |
Notes receivable, fair value disclosure | 389,200,000 |  | 381,700,000 | $ 387,400,000 |
BAM Surplus Notes |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |
Distribution received | $ 0 | $ 26,200,000 |  |  |
BAM Surplus Notes | Surplus Notes |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |
Basis spread on variable rate | 3.00% |  |  |  |
Stated margin |  |  |  | 10.00% | 8.20%
Debt | $ 300,900,000 |  | 300,900,000 |  |
Interest receivable | $ 202,300,000 |  | $ 194,800,000 |  |
BAM Surplus Notes | Surplus Notes | Discount Rate |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |
Debt instrument, measurement input | 0.0800 |  | 0.0810 |  |
Subsidiary - HG Global |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |
Purchase of surplus notes | $ 503,000,000 |  |  |  |
Percentage of risk premium ceded | 60.00% |  |  |  |
Renegotiation period | 5 years |  |  |  |
Percent over a target trust balance | 102.00% |  |  |  |
Subsidiary - HG Global | Regulation 114 |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |
Assets held-in-trust | $ 363,400,000 |  | $ 352,100,000 |  |
Supplement trust target | 603,000,000 |  |  |  |
Subsidiary - HG Global | Supplemental Trust |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |
Assets held-in-trust | $ 612,800,000 |  | $ 598,000,000 |  |
Subsidiary - HG Global | Maximum |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |
Percentage of par value of policy reinsured | 15.00% |  |  |  |
Variable Interest Entity, Primary Beneficiary - Build America Mutual Assurance Company | Fidus Re Ltd. |  |  |  |  |
Guarantor Obligations [Line Items] |  |  |  |  |
Reinsured amount | $ 125,000,000 |  |  |  |

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