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Loss and Loss Adjustment Expense Reserves - Incurred Loss and Allocated LAE, Net of Reinsurance (Details) - P&C Insurance and Reinsurance (Ark/WM Outrigger) $ in Millions | Dec. 31, 2025 USD ($) claim | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
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Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 1,518.1 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | 942.2 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2016, net of reinsurance | 2.4 |  |  |  |  |  |  |  |  |
Loss and LAE reserves, net of reinsurance | 578.3 |  |  |  |  |  |  |  |  |
Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | 1,001.6 | $ 439.2 |  |  |  |  |  |  |  |
All outstanding liabilities before 2016, net of reinsurance | 6.6 |  |  |  |  |  |  |  |  |
Loss and LAE reserves, net of reinsurance | 569.0 |  |  |  |  |  |  |  |  |
Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 918.1 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | 411.0 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2016, net of reinsurance | 1.1 |  |  |  |  |  |  |  |  |
Loss and LAE reserves, net of reinsurance | 508.2 |  |  |  |  |  |  |  |  |
Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 303.2 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | 76.2 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2016, net of reinsurance | 3.6 |  |  |  |  |  |  |  |  |
Loss and LAE reserves, net of reinsurance | 230.6 |  |  |  |  |  |  |  |  |
Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 137.0 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | 110.9 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2016, net of reinsurance | 31.0 |  |  |  |  |  |  |  |  |
Loss and LAE reserves, net of reinsurance | 57.1 |  |  |  |  |  |  |  |  |
2016 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 18.8 | 18.8 | $ 18.8 | $ 18.8 | $ 18.9 | $ 18.7 | $ 18.7 | $ 18.6 | $ 17.8 | $ 22.7
Total IBNR plus expected development on reported claims | $ 0.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,434 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 18.4 | 18.4 | 18.2 | 18.0 | 17.4 | 17.1 | 17.0 | 16.6 | 13.3 | 8.6
2016 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 13.8 | 13.7 | 14.0 | 14.5 | 15.2 | 14.6 | 14.9 | 16.0 | 20.0 | 23.8
Total IBNR plus expected development on reported claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,776 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 13.8 | 13.8 | 13.8 | 13.8 | 14.1 | 13.4 | 13.3 | 12.9 | 10.2 | 5.6
2016 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 12.2 | 12.5 | 8.6 | 9.1 | 12.0 | 12.0 | 11.4 | 11.1 | 14.5 | 18.5
Total IBNR plus expected development on reported claims | $ 0.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,936 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 11.8 | 11.8 | 8.4 | 8.7 | 10.5 | 10.4 | 10.0 | 9.2 | 8.0 | 3.2
2016 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 11.9 | 11.8 | 10.1 | 9.2 | 9.2 | 9.1 | 9.0 | 8.9 | 8.3 | 8.8
Total IBNR plus expected development on reported claims | $ 0.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,606 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 10.3 | 9.7 | 8.1 | 6.5 | 5.3 | 4.6 | 4.0 | 2.3 | 1.0 | 0.2
2016 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 38.1 | 37.5 | 37.5 | 37.7 | 38.6 | 38.9 | 38.6 | 40.5 | 32.3 | 32.6
Total IBNR plus expected development on reported claims | $ 1.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,156 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 34.1 | 32.5 | 31.0 | 28.8 | 27.8 | 25.4 | 22.7 | 17.7 | 10.2 | $ 3.9
2017 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 43.3 | 43.9 | 44.3 | 42.9 | 43.4 | 44.8 | 45.8 | 38.3 | 31.6 |
Total IBNR plus expected development on reported claims | $ 15.6 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,629 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 29.3 | 28.7 | 25.9 | 27.7 | 29.9 | 33.1 | 31.9 | 26.1 | 17.0 |
2017 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 16.4 | 16.4 | 16.3 | 16.0 | 16.9 | 17.3 | 17.9 | 19.7 | 26.5 |
Total IBNR plus expected development on reported claims | $ 0.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,141 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 15.9 | 14.6 | 14.3 | 14.3 | 14.4 | 14.4 | 13.1 | 11.3 | 5.2 |
2017 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 11.1 | 11.2 | 10.6 | 10.9 | 11.9 | 11.8 | 12.3 | 13.2 | 18.3 |
Total IBNR plus expected development on reported claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,201 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 9.9 | 9.9 | 9.3 | 9.5 | 8.8 | 8.8 | 8.6 | 6.8 | 3.3 |
2017 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 10.6 | 10.9 | 10.7 | 10.5 | 9.1 | 9.3 | 10.8 | 11.7 | 11.6 |
Total IBNR plus expected development on reported claims | $ 0.7 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,693 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 9.1 | 8.3 | 7.5 | 5.7 | 4.2 | 3.4 | 2.8 | 1.7 | 0.8 |
2017 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 27.9 | 28.5 | 28.3 | 29.9 | 31.6 | 32.1 | 31.5 | 34.0 | 30.7 |
Total IBNR plus expected development on reported claims | $ 2.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,606 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 24.8 | 23.5 | 22.8 | 22.5 | 21.4 | 18.5 | 14.7 | 9.4 | $ 3.2 |
2018 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 49.0 | 47.0 | 47.0 | 47.4 | 47.4 | 49.7 | 47.8 | 41.4 |  |
Total IBNR plus expected development on reported claims | $ 2.7 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,293 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 45.2 | 44.2 | 43.4 | 41.4 | 40.6 | 40.6 | 32.7 | 15.8 |  |
2018 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 17.0 | 17.4 | 18.4 | 18.0 | 18.5 | 18.1 | 20.6 | 26.2 |  |
Total IBNR plus expected development on reported claims | $ 0.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,245 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 16.3 | 16.1 | 15.9 | 16.0 | 15.3 | 14.6 | 12.9 | 2.7 |  |
2018 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 17.5 | 16.9 | 15.9 | 15.1 | 16.2 | 17.0 | 16.6 | 14.7 |  |
Total IBNR plus expected development on reported claims | $ 0.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,129 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 14.8 | 14.4 | 13.2 | 12.0 | 10.6 | 10.2 | 8.5 | 2.9 |  |
2018 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 10.5 | 9.4 | 9.2 | 8.6 | 10.9 | 11.1 | 13.3 | 12.9 |  |
Total IBNR plus expected development on reported claims | $ 0.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,175 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 8.0 | 7.1 | 6.2 | 4.3 | 4.3 | 3.5 | 1.4 | 0.3 |  |
2018 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 28.2 | 27.8 | 28.0 | 26.2 | 26.6 | 27.3 | 28.2 | 33.6 |  |
Total IBNR plus expected development on reported claims | $ 2.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,284 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 22.7 | 21.3 | 18.2 | 16.3 | 14.9 | 12.6 | 7.4 | $ 3.4 |  |
2019 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 21.5 | 23.2 | 23.5 | 24.2 | 27.4 | 31.7 | 34.6 |  |  |
Total IBNR plus expected development on reported claims | $ 0.5 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,030 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 19.9 | 20.9 | 19.6 | 18.8 | 18.6 | 17.0 | 6.9 |  |  |
2019 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 21.8 | 21.6 | 22.3 | 21.9 | 22.1 | 22.0 | 24.2 |  |  |
Total IBNR plus expected development on reported claims | $ 0.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,413 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 19.3 | 18.4 | 15.7 | 14.7 | 12.9 | 10.9 | 3.4 |  |  |
2019 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 26.8 | 20.0 | 30.1 | 25.9 | 18.9 | 19.8 | 22.1 |  |  |
Total IBNR plus expected development on reported claims | $ 0.7 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,396 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 19.8 | 17.7 | 25.2 | 18.5 | 7.6 | 7.2 | 5.0 |  |  |
2019 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 14.4 | 13.0 | 11.4 | 10.6 | 12.3 | 13.7 | 14.8 |  |  |
Total IBNR plus expected development on reported claims | $ 1.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,062 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 10.2 | 8.3 | 5.7 | 3.0 | 2.3 | 1.4 | 0.3 |  |  |
2019 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 22.5 | 23.7 | 23.6 | 24.9 | 23.4 | 23.3 | 26.5 |  |  |
Total IBNR plus expected development on reported claims | $ 4.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 976 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 17.3 | 15.9 | 15.1 | 12.1 | 7.8 | 5.8 | $ 3.3 |  |  |
2020 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 84.8 | 81.0 | 79.1 | 75.3 | 76.3 | 78.1 |  |  |  |
Total IBNR plus expected development on reported claims | $ 6.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,664 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 72.4 | 67.4 | 56.3 | 47.5 | 34.5 | 11.4 |  |  |  |
2020 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 27.6 | 27.6 | 27.9 | 29.1 | 27.7 | 30.4 |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,594 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 23.2 | 22.4 | 18.9 | 16.3 | 12.9 | 3.2 |  |  |  |
2020 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 17.7 | 17.3 | 20.4 | 19.3 | 23.5 | 24.5 |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,028 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 19.2 | 18.5 | 18.8 | 13.4 | 11.0 | 5.4 |  |  |  |
2020 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 9.5 | 8.8 | 9.2 | 10.9 | 12.1 | 13.5 |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.7 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 731 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 6.0 | 5.3 | 3.3 | 2.0 | 1.0 | 0.5 |  |  |  |
2020 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 9.2 | 9.5 | 10.9 | 13.9 | 12.3 | 15.9 |  |  |  |
Total IBNR plus expected development on reported claims | $ 2.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 573 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 6.5 | 6.3 | 6.0 | 3.1 | 1.3 | $ 0.8 |  |  |  |
2021 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 169.7 | 171.5 | 168.9 | 156.8 | 173.0 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 8.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,533 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 150.9 | 145.6 | 132.3 | 87.5 | 31.0 |  |  |  |  |
2021 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 79.8 | 75.6 | 68.4 | 70.5 | 87.7 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 3.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,530 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 64.4 | 52.7 | 38.9 | 24.9 | 6.4 |  |  |  |  |
2021 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 41.7 | 44.0 | 51.8 | 63.0 | 71.8 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 6.6 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,735 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 35.3 | 34.6 | 35.8 | 24.1 | 5.1 |  |  |  |  |
2021 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 21.7 | 16.3 | 16.6 | 22.4 | 21.4 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 4.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,050 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 12.6 | 9.6 | 3.1 | 0.9 | 0.5 |  |  |  |  |
2021 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 3.9 | 4.5 | 5.5 | 7.0 | 10.5 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.5 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 284 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 2.4 | 2.3 | 1.9 | 1.7 | $ 0.5 |  |  |  |  |
2022 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 281.9 | 280.0 | 269.6 | 245.7 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 9.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,100 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 250.2 | 232.0 | 194.5 | 71.7 |  |  |  |  |  |
2022 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 218.6 | 157.5 | 154.9 | 150.8 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 56.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,083 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 145.5 | 98.6 | 66.7 | 12.3 |  |  |  |  |  |
2022 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 179.6 | 172.6 | 178.5 | 181.9 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 58.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,577 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 113.2 | 84.9 | 62.5 | 16.1 |  |  |  |  |  |
2022 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 17.3 | 34.7 | 38.1 | 33.0 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 9.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,774 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 3.6 | 2.5 | 1.6 | 0.5 |  |  |  |  |  |
2022 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 2.3 | 2.6 | 2.6 | 0.8 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 80 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 0.9 | 0.7 | 0.6 | $ 0.3 |  |  |  |  |  |
2023 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 130.4 | 178.6 | 216.9 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 20.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,688 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 78.5 | 53.8 | 20.2 |  |  |  |  |  |  |
2023 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 123.2 | 189.9 | 198.6 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 36.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,341 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 61.3 | 42.7 | 10.6 |  |  |  |  |  |  |
2023 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 153.4 | 199.4 | 216.6 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 41.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,734 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 109.1 | 76.3 | 19.2 |  |  |  |  |  |  |
2023 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 57.1 | 65.9 | 61.0 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 39.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,234 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 10.8 | 5.6 | 0.9 |  |  |  |  |  |  |
2023 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 3.1 | 3.6 | 2.7 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 40 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 1.1 | 1.0 | $ 0.9 |  |  |  |  |  |  |
2024 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 324.6 | 364.8 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 106.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,495 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 134.6 | 55.4 |  |  |  |  |  |  |  |
2024 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 248.1 | 243.3 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 138.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,195 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 60.1 | 21.4 |  |  |  |  |  |  |  |
2024 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 231.3 | 223.2 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 133.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,798 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 53.8 | 28.9 |  |  |  |  |  |  |  |
2024 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 82.0 | 60.0 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 71.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,171 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 4.6 | 1.9 |  |  |  |  |  |  |  |
2024 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 1.1 | 1.2 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.5 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 20 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 0.5 | $ 0.5 |  |  |  |  |  |  |  |
2025 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 394.1 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 171.7 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,899 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 142.8 |  |  |  |  |  |  |  |  |
2025 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 235.3 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 184.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,618 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 19.4 |  |  |  |  |  |  |  |  |
2025 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 226.8 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 169.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,831 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 24.1 |  |  |  |  |  |  |  |  |
2025 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 68.2 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 63.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,723 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 1.0 |  |  |  |  |  |  |  |  |
2025 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 0.7 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 41 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 0.6 |  |  |  |  |  |  |  |  |

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