Third-Party Reinsurance - Effects of Reinsurance (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
|
| Written premiums: | ||||
| Direct | $ 13.6 | $ 24.1 | ||
| Assumed | 0.0 | 0.0 | ||
| Gross written premiums | 13.6 | 24.1 | ||
| Earned premiums: | ||||
| Direct | 8.5 | 15.8 | ||
| Assumed | 0.5 | 1.0 | ||
| Gross earned premiums | 9.0 | 16.8 | ||
| Net earned premiums | $ 375.2 | 343.9 | $ 770.2 | 662.9 |
| Loss and LAE: | ||||
| Net incurred loss and LAE | 166.5 | 183.9 | 428.3 | 369.7 |
| P&C Insurance and Reinsurance (Ark/WM Outrigger) | ||||
| Written premiums: | ||||
| Direct | 356.6 | 339.4 | 773.4 | 624.4 |
| Assumed | 458.6 | 357.6 | 1,149.4 | 944.7 |
| Gross written premiums | 815.2 | 697.0 | 1,922.8 | 1,569.1 |
| Ceded | (236.6) | (194.2) | (616.5) | (468.3) |
| Net written premiums | 578.6 | 502.8 | 1,306.3 | 1,100.8 |
| Earned premiums: | ||||
| Direct | 260.1 | 219.5 | 506.4 | 413.9 |
| Assumed | 209.0 | 180.3 | 423.1 | 372.7 |
| Gross earned premiums | 469.1 | 399.8 | 929.5 | 786.6 |
| Ceded | (104.9) | (81.5) | (207.3) | (165.5) |
| Net earned premiums | 364.2 | 318.3 | 722.2 | 621.1 |
| Loss and LAE: | ||||
| Gross | 197.0 | 248.7 | 520.2 | 502.0 |
| Ceded | (33.0) | (73.0) | (122.7) | (146.3) |
| Net incurred loss and LAE | 164.0 | 175.7 | 397.5 | 355.7 |
| Effects of Reinsurance Footnotes [Abstract] | ||||
| Ceded premiums written | 236.6 | 194.2 | 616.5 | 468.3 |
| Ceded premiums earned | 104.9 | 81.5 | 207.3 | 165.5 |
| Ceded | 33.0 | 73.0 | 122.7 | 146.3 |
| P&C Insurance and Reinsurance (Ark/WM Outrigger) | Ark | ||||
| Written premiums: | ||||
| Ceded | (42.6) | (38.9) | (80.1) | (73.2) |
| Earned premiums: | ||||
| Ceded | (7.1) | (7.5) | (19.1) | (17.8) |
| Loss and LAE: | ||||
| Ceded | 1.7 | (0.3) | 21.9 | 0.4 |
| Effects of Reinsurance Footnotes [Abstract] | ||||
| Ceded premiums written | 42.6 | 38.9 | 80.1 | 73.2 |
| Ceded premiums earned | 7.1 | 7.5 | 19.1 | 17.8 |
| Ceded | $ (1.7) | $ 0.3 | $ (21.9) | $ (0.4) |
| X | ||||||||||
- 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/2003/role/exampleRef
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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/2003/role/exampleRef
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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/2003/role/exampleRef
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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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