Third-Party Reinsurance - Effects of Reinsurance (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Earned premiums: | ||||
| Net earned premiums | $ 384.6 | $ 375.2 | $ 770.2 | |
| Loss and LAE: | ||||
| Net incurred loss and LAE | 175.7 | 166.5 | 428.3 | |
| P&C Insurance and Reinsurance (Ark/WM Outrigger) | ||||
| Written premiums: | ||||
| Direct | 373.6 | 356.6 | $ 730.9 | 773.4 |
| Assumed | 403.9 | 458.6 | 1,137.5 | 1,149.4 |
| Gross written premiums | 777.5 | 815.2 | 1,868.4 | 1,922.8 |
| Ceded | (240.1) | (236.6) | (740.9) | (616.5) |
| Net written premiums | 537.4 | 578.6 | 1,127.5 | 1,306.3 |
| Earned premiums: | ||||
| Direct | 288.2 | 260.1 | 554.9 | 506.4 |
| Assumed | 242.3 | 209.0 | 479.1 | 423.1 |
| Gross earned premiums | 530.5 | 469.1 | 1,034.0 | 929.5 |
| Ceded | (154.3) | (104.9) | (284.0) | (207.3) |
| Net earned premiums | 376.2 | 364.2 | 750.0 | 722.2 |
| Loss and LAE: | ||||
| Gross | 354.8 | 197.0 | 618.8 | 520.2 |
| Ceded | (179.2) | (33.0) | (236.5) | (122.7) |
| Net incurred loss and LAE | 175.6 | 164.0 | 382.3 | 397.5 |
| Effects of Reinsurance Footnotes [Abstract] | ||||
| Ceded premiums written | 240.1 | 236.6 | 740.9 | 616.5 |
| Ceded premiums earned | 154.3 | 104.9 | 284.0 | 207.3 |
| Ceded | 179.2 | 33.0 | 236.5 | 122.7 |
| P&C Insurance and Reinsurance (Ark/WM Outrigger) | Ark | ||||
| Written premiums: | ||||
| Ceded | (0.4) | (42.6) | (0.4) | (80.1) |
| Earned premiums: | ||||
| Ceded | (0.8) | (7.1) | (3.5) | (19.1) |
| Loss and LAE: | ||||
| Ceded | (0.1) | (1.7) | 0.2 | 21.9 |
| Effects of Reinsurance Footnotes [Abstract] | ||||
| Ceded premiums written | 0.4 | 42.6 | 0.4 | 80.1 |
| Ceded premiums earned | 0.8 | 7.1 | 3.5 | 19.1 |
| Ceded | $ 0.1 | $ 1.7 | $ (0.2) | $ (21.9) |
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- Definition Amount of earned premiums assumed from other entities. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of written premiums assumed from other entities. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of earned premiums ceded to other entities. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of written premiums ceded to other entities. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums earned. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums written. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred and costs incurred in the claim settlement process. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount, before effect of policies assumed or ceded, of expense related to provision for policy benefits and costs incurred. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of direct and assumed premiums written. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums written. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Amount of reduction of provision for policy benefits and costs incurred for policies ceded. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Effects of Reinsurance Footnotes No definition available.
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- Definition Gross Premiums Earned No definition available.
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- Definition Losses and Loss Adjustment Expense No definition available.
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- Details
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- Details
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