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v3.25.4

Variable Interest Entities (Details) - USD ($) $ in Millions | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2025 | Sep. 02, 2025 | Dec. 31, 2024 | Jul. 01, 2024 | Jun. 30, 2024
Variable Interest Entity [Line Items] |  |  |  |  |
Assets held-in-trust | $ 1,006.5 |  | $ 950.1 |  |
Subsidiary - WM Outrigger Re | Preferred stocks |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Basic ownership | 100.00% |  | 100.00% |  |
Subsidiary - Distinguished Managing General Agent |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Basic ownership | 55.50% | 55.50% |  |  |
Bamboo CRV |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Expected capital contribution | $ 10.0 |  |  |  |
BAM Surplus Notes | Surplus Notes |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Interest rate |  |  |  | 10.00% | 8.20%
Subsidiary - HG Global |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Purchase of surplus notes | $ 503.0 |  |  |  |
Subsidiary - HG Global | Maximum |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Percentage of par value of policy reinsured | 15.00% |  |  |  |
Outrigger Re |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Short-term investments, at fair value | $ 245.7 |  | $ 203.7 |  |
Bamboo CRV | Variable Interest Entity, Not Primary Beneficiary |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Partnership interest, carrying value | $ 250.0 |  |  |  |
PassportCard/DavidShield | Variable Interest Entity, Not Primary Beneficiary |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Ownership interest | 53.80% |  |  |  |
Partnership interest, carrying value | $ 180.1 |  |  |  |
BroadStreet | Variable Interest Entity, Not Primary Beneficiary |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Ownership interest | 10.90% |  |  |  |
Partnership interest, carrying value | $ 160.0 |  |  |  |
Elementum | Variable Interest Entity, Not Primary Beneficiary |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Ownership interest | 26.60% |  |  |  |
Partnership interest, carrying value | $ 35.0 |  |  |  |
Limited Partnerships | Variable Interest Entity, Not Primary Beneficiary |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Partnership interest, carrying value | $ 251.2 |  |  |  |

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