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v3.24.1.u1

Third-Party Reinsurance - Effects of Reinsurance (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Earned premiums: |  |
Net earned premiums | $ 319.0 | $ 262.8
Loss and loss adjustment expenses: |  |
Net incurred loss and loss adjustment expenses | 185.8 | 147.8
P&C Insurance and Reinsurance (Ark/WM Outrigger) |  |
Written premiums: |  |
Direct | 285.0 | 246.2
Assumed | 587.1 | 563.2
Gross written premiums | 872.1 | 809.4
Ceded | (274.1) | (195.2)
Net written premiums | 598.0 | 614.2
Earned premiums: |  |
Direct | 194.4 | 150.4
Assumed | 192.4 | 162.1
Gross earned premiums | 386.8 | 312.5
Ceded | (84.0) | (57.4)
Net earned premiums | 302.8 | 255.1
Loss and loss adjustment expenses: |  |
Gross | 253.3 | 162.4
Ceded | (73.3) | (14.6)
Net incurred loss and loss adjustment expenses | 180.0 | 147.8
P&C Insurance and Reinsurance (Ark/WM Outrigger) | Ark |  |
Written premiums: |  |
Ceded | (34.3) | 44.1
Earned premiums: |  |
Ceded | (10.3) | 5.2
Loss and loss adjustment expenses: |  |
Ceded | $ (0.7) | $ 0.2

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