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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, 2024 USD ($) claim | Dec. 31, 2023 USD ($) | 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 ($) | Dec. 31, 2015 USD ($)
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Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 1,207.6 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | 672.4 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2015, net of reinsurance | 1.5 |  |  |  |  |  |  |  |  |
Loss and LAE reserves, net of reinsurance | 536.7 |  |  |  |  |  |  |  |  |
Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | 765.7 | $ 307.3 |  |  |  |  |  |  |  |
All outstanding liabilities before 2015, net of reinsurance | 4.7 |  |  |  |  |  |  |  |  |
Loss and LAE reserves, net of reinsurance | 463.1 |  |  |  |  |  |  |  |  |
Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 716.0 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | 299.6 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2015, net of reinsurance | 0.6 |  |  |  |  |  |  |  |  |
Loss and LAE reserves, net of reinsurance | 417.0 |  |  |  |  |  |  |  |  |
Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 237.6 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | 64.5 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2015, net of reinsurance | 4.9 |  |  |  |  |  |  |  |  |
Loss and LAE reserves, net of reinsurance | 178.0 |  |  |  |  |  |  |  |  |
Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 177.9 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | 139.6 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2015, net of reinsurance | 28.2 |  |  |  |  |  |  |  |  |
Loss and LAE reserves, net of reinsurance | 66.5 |  |  |  |  |  |  |  |  |
2015 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 16.1 | 16.0 | $ 15.7 | $ 15.8 | $ 16.0 | $ 16.0 | $ 16.2 | $ 17.2 | $ 18.1 | $ 19.1
Total IBNR plus expected development on reported claims | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,829 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 15.6 | 15.4 | 15.0 | 15.0 | 14.8 | 14.5 | 14.6 | 13.4 | 12.2 | 6.9
2015 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 12.7 | 12.7 | 12.9 | 12.7 | 12.8 | 12.7 | 13.3 | 16.1 | 17.4 | 21.7
Total IBNR plus expected development on reported claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,243 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 11.6 | 11.6 | 11.5 | 10.9 | 10.5 | 10.4 | 11.0 | 9.6 | 7.8 | 4.0
2015 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 11.3 | 8.1 | 8.9 | 11.1 | 11.2 | 11.0 | 10.7 | 12.3 | 14.6 | 17.3
Total IBNR plus expected development on reported claims | $ 0.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,841 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 9.3 | 6.2 | 6.4 | 8.1 | 8.1 | 8.0 | 8.0 | 7.6 | 7.0 | 4.0
2015 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 7.4 | 7.5 | 7.3 | 7.0 | 7.1 | 7.4 | 8.1 | 8.2 | 9.7 | 9.6
Total IBNR plus expected development on reported claims | $ 0.5 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,306 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 6.3 | 6.1 | 5.5 | 5.1 | 4.9 | 4.7 | 4.4 | 3.2 | 2.4 | 1.8
2015 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 39.4 | 40.2 | 39.1 | 36.7 | 37.3 | 36.3 | 36.6 | 33.1 | 31.9 | 36.4
Total IBNR plus expected development on reported claims | $ 1.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,950 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 35.8 | 35.3 | 33.0 | 28.9 | 27.3 | 24.6 | 21.4 | 14.5 | 8.2 | $ 4.3
2016 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 18.5 | 18.5 | 18.5 | 18.5 | 18.3 | 18.4 | 18.2 | 17.5 | 22.2 |
Total IBNR plus expected development on reported claims | $ 0.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,433 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 18.1 | 17.9 | 17.7 | 17.1 | 16.8 | 16.7 | 16.3 | 13.0 | 8.5 |
2016 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 13.3 | 13.6 | 14.1 | 14.8 | 14.3 | 14.6 | 15.6 | 19.5 | 23.4 |
Total IBNR plus expected development on reported claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,772 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 13.4 | 13.4 | 13.4 | 13.7 | 13.1 | 13.0 | 12.6 | 10.0 | 5.5 |
2016 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 12.3 | 8.5 | 8.9 | 11.8 | 11.8 | 11.3 | 10.9 | 14.3 | 18.2 |
Total IBNR plus expected development on reported claims | $ 0.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,936 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 11.7 | 8.3 | 8.5 | 10.3 | 10.3 | 9.9 | 9.1 | 7.9 | 3.2 |
2016 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 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 | $ 0.5 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,588 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 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 | 37.4 | 37.3 | 37.6 | 38.4 | 38.7 | 38.4 | 40.3 | 32.1 | 32.4 |
Total IBNR plus expected development on reported claims | $ 2.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,150 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 32.4 | 30.9 | 28.7 | 27.8 | 25.3 | 22.7 | 17.7 | 10.1 | $ 3.9 |
2017 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 43.4 | 43.8 | 42.3 | 42.8 | 44.2 | 45.2 | 37.7 | 31.1 |  |
Total IBNR plus expected development on reported claims | $ 15.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,624 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 28.2 | 25.4 | 27.1 | 29.4 | 32.7 | 31.5 | 25.7 | 16.8 |  |
2017 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 16.1 | 16.0 | 15.8 | 16.6 | 16.9 | 17.6 | 19.3 | 26.0 |  |
Total IBNR plus expected development on reported claims | $ 0.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,139 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 14.3 | 14.0 | 14.1 | 14.1 | 14.0 | 12.8 | 11.1 | 5.1 |  |
2017 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 10.9 | 10.3 | 10.6 | 11.6 | 11.4 | 11.9 | 12.8 | 17.9 |  |
Total IBNR plus expected development on reported claims | $ 0.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,195 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 9.6 | 8.9 | 9.2 | 8.5 | 8.5 | 8.3 | 6.5 | 3.1 |  |
2017 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 10.9 | 10.6 | 10.5 | 9.0 | 9.3 | 10.8 | 11.7 | 11.5 |  |
Total IBNR plus expected development on reported claims | $ 0.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,667 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 8.3 | 7.5 | 5.7 | 4.2 | 3.4 | 2.7 | 1.7 | 0.8 |  |
2017 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 28.4 | 28.2 | 29.8 | 31.5 | 32.0 | 31.3 | 33.8 | 30.5 |  |
Total IBNR plus expected development on reported claims | $ 2.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,604 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 23.5 | 22.8 | 22.5 | 21.3 | 18.4 | 14.6 | 9.4 | $ 3.2 |  |
2018 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 46.4 | 46.3 | 46.8 | 46.7 | 49.0 | 47.1 | 40.7 |  |  |
Total IBNR plus expected development on reported claims | $ 1.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,288 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 43.6 | 42.8 | 40.8 | 40.0 | 40.1 | 32.2 | 15.6 |  |  |
2018 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 16.7 | 17.7 | 17.3 | 17.8 | 17.4 | 19.9 | 25.4 |  |  |
Total IBNR plus expected development on reported claims | $ 0.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,238 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 15.4 | 15.3 | 15.3 | 14.6 | 13.9 | 12.4 | 2.6 |  |  |
2018 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 16.6 | 15.7 | 14.8 | 15.9 | 16.6 | 16.2 | 14.4 |  |  |
Total IBNR plus expected development on reported claims | $ 0.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,122 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 14.1 | 13.0 | 11.8 | 10.4 | 9.9 | 8.2 | 2.7 |  |  |
2018 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 9.4 | 9.1 | 8.6 | 10.8 | 11.1 | 13.3 | 12.9 |  |  |
Total IBNR plus expected development on reported claims | $ 1.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,147 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 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 | 27.7 | 27.9 | 26.1 | 26.5 | 27.2 | 28.1 | 33.5 |  |  |
Total IBNR plus expected development on reported claims | $ 3.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,280 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 21.3 | 18.2 | 16.2 | 14.9 | 12.6 | 7.4 | $ 3.4 |  |  |
2019 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 22.8 | 23.2 | 23.8 | 27.0 | 31.2 | 33.9 |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.6 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,024 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 20.6 | 19.3 | 18.5 | 18.3 | 16.7 | 6.8 |  |  |  |
2019 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 21.2 | 21.9 | 21.4 | 21.6 | 21.6 | 23.7 |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.5 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,393 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 18.1 | 15.3 | 14.3 | 12.6 | 10.6 | 3.3 |  |  |  |
2019 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 19.9 | 30.1 | 25.6 | 18.6 | 19.4 | 21.6 |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,387 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 17.6 | 25.1 | 18.2 | 7.4 | 6.9 | 4.8 |  |  |  |
2019 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 13.0 | 11.4 | 10.6 | 12.3 | 13.7 | 14.8 |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.7 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,019 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 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 | 23.6 | 23.5 | 24.8 | 23.3 | 23.2 | 26.4 |  |  |  |
Total IBNR plus expected development on reported claims | $ 5.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 973 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 15.8 | 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 | 79.5 | 77.6 | 74.5 | 75.1 | 76.9 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 9.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,646 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 66.5 | 55.6 | 46.9 | 33.9 | 11.2 |  |  |  |  |
2020 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 27.1 | 27.4 | 28.5 | 27.1 | 29.7 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,582 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 21.9 | 18.5 | 16.0 | 12.7 | 3.1 |  |  |  |  |
2020 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 16.7 | 19.5 | 18.6 | 22.8 | 23.7 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,017 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 17.7 | 17.7 | 12.9 | 10.5 | 5.0 |  |  |  |  |
2020 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 8.8 | 9.2 | 10.8 | 12.0 | 13.5 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 2.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 665 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 5.3 | 3.3 | 2.0 | 1.0 | 0.5 |  |  |  |  |
2020 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 9.5 | 10.9 | 13.8 | 12.2 | 15.8 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 2.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 567 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 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 | 168.0 | 165.3 | 153.7 | 170.0 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 7.5 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,509 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 142.7 | 129.8 | 86.5 | 30.7 |  |  |  |  |  |
2021 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 74.5 | 67.3 | 69.3 | 86.2 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 4.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,505 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 51.9 | 38.2 | 24.3 | 6.3 |  |  |  |  |  |
2021 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 43.8 | 51.4 | 62.1 | 70.3 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 10.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,725 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 34.6 | 35.5 | 23.9 | 5.0 |  |  |  |  |  |
2021 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 16.3 | 16.6 | 22.4 | 21.4 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 6.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 961 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 9.6 | 3.1 | 0.9 | 0.5 |  |  |  |  |  |
2021 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 4.5 | 5.4 | 7.0 | 10.4 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 283 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 2.3 | 1.8 | 1.7 | $ 0.5 |  |  |  |  |  |
2022 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 277.3 | 266.9 | 241.5 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 12.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,044 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 229.4 | 191.9 | 69.4 |  |  |  |  |  |  |
2022 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 156.0 | 153.6 | 149.7 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 31.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,968 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 97.7 | 66.2 | 12.2 |  |  |  |  |  |  |
2022 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 168.4 | 174.8 | 180.3 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 77.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,496 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 82.5 | 61.7 | 16.0 |  |  |  |  |  |  |
2022 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 34.6 | 38.0 | 32.9 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 27.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,558 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 2.4 | 1.5 | 0.4 |  |  |  |  |  |  |
2022 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 2.5 | 2.6 | 0.8 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.6 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 80 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 0.7 | 0.5 | $ 0.3 |  |  |  |  |  |  |
2023 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 176.1 | 213.9 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 77.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,598 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 52.9 | 19.9 |  |  |  |  |  |  |  |
2023 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 188.2 | 197.0 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 115.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,138 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 42.1 | 10.5 |  |  |  |  |  |  |  |
2023 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 197.4 | 214.5 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 94.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,641 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 75.2 | 18.4 |  |  |  |  |  |  |  |
2023 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 65.9 | 60.9 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 57.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,792 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 5.6 | 0.9 |  |  |  |  |  |  |  |
2023 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 3.6 | 2.7 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 2.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 40 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 1.0 | $ 0.9 |  |  |  |  |  |  |  |
2024 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 359.5 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 202.7 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,614 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 54.8 |  |  |  |  |  |  |  |  |
2024 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 239.9 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 182.6 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,485 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 20.9 |  |  |  |  |  |  |  |  |
2024 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 218.7 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 141.6 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,292 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 27.3 |  |  |  |  |  |  |  |  |
2024 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 59.5 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 54.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,170 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 1.9 |  |  |  |  |  |  |  |  |
2024 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 1.3 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.7 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 22 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 0.5 |  |  |  |  |  |  |  |  |

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