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v3.25.4

Third-Party Reinsurance - Effects of Reinsurance (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Written premiums: |  |  |
Direct |  | $ 24.1 | $ 58.6
Assumed |  | 31.9 | 0.0
Gross written premiums |  | 56.0 | 58.6
Earned premiums: |  |  |
Direct |  | 15.8 | 28.7
Assumed |  | 15.9 | 2.5
Gross earned premiums |  | 31.7 | 31.2
Net earned premiums | $ 1,777.1 | 1,691.6 | 1,440.9
Loss and LAE: |  |  |
Net incurred loss and LAE | 882.2 | 888.5 | 726.8
Ark Insurance Holdings Limited/Outrigger |  |  |
Written premiums: |  |  |
Direct | 1,260.1 | 1,101.5 | 931.9
Assumed | 1,297.1 | 1,105.5 | 966.5
Gross written premiums | 2,557.2 | 2,207.0 | 1,898.4
Ceded | (745.6) | (527.9) | (377.5)
Net written premiums | 1,811.6 | 1,679.1 | 1,520.9
Earned premiums: |  |  |
Direct | 1,130.9 | 1,004.2 | 848.1
Assumed | 1,198.9 | 1,088.2 | 925.6
Gross earned premiums | 2,329.8 | 2,092.4 | 1,773.7
Ceded | (632.4) | (504.6) | (364.0)
Net earned premiums | 1,697.4 | 1,587.8 | 1,409.7
Loss and LAE: |  |  |
Gross | 1,118.6 | 1,056.7 | 782.5
Ceded | (274.4) | (200.9) | (55.7)
Net incurred loss and LAE | 844.2 | 855.8 | 726.8
Effects of Reinsurance Footnotes [Abstract] |  |  |
Ceded premiums written | 745.6 | 527.9 | 377.5
Ceded premiums earned | 632.4 | 504.6 | 364.0
Ceded | 274.4 | 200.9 | 55.7
Ark Insurance Holdings Limited/Outrigger | Ark |  |  |
Written premiums: |  |  |
Ceded | (84.2) | (86.5) | 110.0
Earned premiums: |  |  |
Ceded | (84.6) | (88.0) | 104.3
Loss and LAE: |  |  |
Ceded | (25.4) | (29.9) | 15.6
Effects of Reinsurance Footnotes [Abstract] |  |  |
Ceded premiums written | 84.2 | 86.5 | (110.0)
Ceded premiums earned | 84.6 | 88.0 | (104.3)
Ceded | $ 25.4 | $ 29.9 | $ (15.6)

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