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Loss and Loss Adjustment Expense Reserves - Incurred Loss and Allocated LAE, Net of Reinsurance (Details) - Ark $ in Millions | Dec. 31, 2023 USD ($) claim | Dec. 31, 2022 USD ($) | 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 ($) | Dec. 31, 2014 USD ($)
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Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 908.0 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | 551.2 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2014, net of reinsurance | 1.9 |  |  |  |  |  |  |  |  |
Loss and LAE reserves, net of reinsurance | 358.7 |  |  |  |  |  |  |  |  |
Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 580.4 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | 240.7 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2014, net of reinsurance | 0.0 |  |  |  |  |  |  |  |  |
Loss and LAE reserves, net of reinsurance | 339.7 |  |  |  |  |  |  |  |  |
Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 543.9 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | 218.5 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2014, net of reinsurance | 6.3 |  |  |  |  |  |  |  |  |
Loss and LAE reserves, net of reinsurance | 331.7 |  |  |  |  |  |  |  |  |
Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 181.5 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | 49.2 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2014, net of reinsurance | 4.8 |  |  |  |  |  |  |  |  |
Loss and LAE reserves, net of reinsurance | 137.1 |  |  |  |  |  |  |  |  |
Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 239.1 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | 186.7 |  |  |  |  |  |  |  |  |
All outstanding liabilities before 2014, net of reinsurance | 28.9 |  |  |  |  |  |  |  |  |
Loss and LAE reserves, net of reinsurance | 81.3 |  |  |  |  |  |  |  |  |
2014 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 28.5 | $ 28.6 | $ 28.6 | $ 28.6 | $ 28.6 | $ 28.5 | $ 28.7 | $ 29.4 | $ 29.5 | $ 32.8
Total IBNR plus expected development on reported claims | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,924 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 28.0 | 28.0 | 28.0 | 28.0 | 27.9 | 27.7 | 27.6 | 27.3 | 25.1 | 13.7
2014 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 43.5 | 43.5 | 43.7 | 43.8 | 43.8 | 41.2 | 40.8 | 41.2 | 44.2 | 46.0
Total IBNR plus expected development on reported claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,359 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 43.7 | 43.4 | 43.1 | 43.2 | 42.4 | 41.1 | 40.5 | 40.1 | 39.3 | 26.5
2014 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 13.6 | 13.9 | 13.8 | 14.0 | 13.7 | 14.1 | 16.3 | 17.2 | 20.2 | 34.4
Total IBNR plus expected development on reported claims | $ (0.3) |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,572 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 13.8 | 13.9 | 13.6 | 13.8 | 13.6 | 14.3 | 14.2 | 13.4 | 12.3 | 5.9
2014 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 7.7 | 7.8 | 7.6 | 7.8 | 7.7 | 8.1 | 8.2 | 8.4 | 9.4 | 13.3
Total IBNR plus expected development on reported claims | $ 0.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,393 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 6.7 | 6.2 | 6.0 | 5.9 | 5.5 | 5.2 | 4.7 | 4.2 | 3.5 | 1.3
2014 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 59.7 | 58.7 | 58.9 | 59.1 | 59.1 | 57.6 | 54.0 | 51.0 | 48.4 | 49.2
Total IBNR plus expected development on reported claims | $ 1.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,947 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 54.9 | 51.9 | 49.4 | 48.7 | 47.0 | 43.2 | 36.5 | 29.6 | 23.2 | $ 6.5
2015 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 16.1 | 15.8 | 15.9 | 16.2 | 16.1 | 16.3 | 17.3 | 18.3 | 19.3 |
Total IBNR plus expected development on reported claims | $ 0.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,829 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 15.5 | 15.1 | 15.1 | 14.9 | 14.7 | 14.7 | 13.5 | 12.3 | 6.9 |
2015 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 8.2 | 9.0 | 11.3 | 11.3 | 11.1 | 10.8 | 12.4 | 14.8 | 17.4 |
Total IBNR plus expected development on reported claims | $ (0.1) |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,841 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 6.3 | 6.5 | 8.2 | 8.2 | 8.1 | 8.1 | 7.7 | 7.1 | 4.0 |
2015 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 12.9 | 13.1 | 12.8 | 13.0 | 12.8 | 13.4 | 16.3 | 17.5 | 21.8 |
Total IBNR plus expected development on reported claims | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,242 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 11.7 | 11.6 | 11.0 | 10.6 | 10.5 | 11.1 | 9.7 | 7.9 | 4.0 |
2015 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 7.5 | 7.3 | 7.0 | 7.2 | 7.4 | 8.1 | 8.2 | 9.8 | 9.6 |
Total IBNR plus expected development on reported claims | $ 0.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,295 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 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 | 40.3 | 39.3 | 36.8 | 37.5 | 36.5 | 36.8 | 33.3 | 32.1 | 36.7 |
Total IBNR plus expected development on reported claims | $ 2.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 35.3 | 33.1 | 29.0 | 27.4 | 24.7 | 21.4 | 14.5 | 8.2 | $ 4.3 |
2016 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 18.7 | 18.8 | 18.8 | 18.6 | 18.6 | 18.5 | 17.7 | 22.5 |  |
Total IBNR plus expected development on reported claims | $ 0.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,428 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 18.1 | 17.9 | 17.3 | 17.0 | 16.9 | 16.5 | 13.2 | 8.6 |  |
2016 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 8.6 | 9.0 | 11.9 | 11.9 | 11.3 | 11.0 | 14.4 | 18.4 |  |
Total IBNR plus expected development on reported claims | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,932 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 8.4 | 8.6 | 10.4 | 10.4 | 9.9 | 9.1 | 8.0 | 3.2 |  |
2016 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 13.8 | 14.2 | 15.0 | 14.4 | 14.7 | 15.8 | 19.7 | 23.6 |  |
Total IBNR plus expected development on reported claims | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,770 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 13.6 | 13.6 | 13.9 | 13.3 | 13.1 | 12.7 | 10.1 | 5.6 |  |
2016 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 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 | 1,553 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 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 | 37.5 | 37.7 | 38.6 | 38.8 | 38.6 | 40.4 | 32.2 | 32.6 |  |
Total IBNR plus expected development on reported claims | $ 2.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,158 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 31.0 | 28.7 | 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 | 44.2 | 42.7 | 43.2 | 44.6 | 45.6 | 38.1 | 31.3 |  |  |
Total IBNR plus expected development on reported claims | $ 15.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,613 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 25.7 | 27.5 | 29.8 | 33.0 | 31.8 | 26.0 | 16.9 |  |  |
2017 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 10.4 | 10.7 | 11.7 | 11.6 | 12.1 | 13.0 | 18.1 |  |  |
Total IBNR plus expected development on reported claims | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,191 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 9.1 | 9.3 | 8.6 | 8.6 | 8.5 | 6.7 | 3.2 |  |  |
2017 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 16.1 | 15.9 | 16.8 | 17.1 | 17.7 | 19.5 | 26.2 |  |  |
Total IBNR plus expected development on reported claims | $ 0.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,133 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 14.1 | 14.2 | 14.2 | 14.2 | 12.9 | 11.2 | 5.1 |  |  |
2017 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 10.7 | 10.5 | 9.1 | 9.4 | 10.8 | 11.7 | 11.6 |  |  |
Total IBNR plus expected development on reported claims | $ 1.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,632 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 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 | 28.3 | 29.9 | 31.6 | 32.1 | 31.4 | 34.0 | 30.6 |  |  |
Total IBNR plus expected development on reported claims | $ 2.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,603 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 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 | 46.7 | 47.1 | 47.0 | 49.3 | 47.4 | 41.0 |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,269 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 43.1 | 41.1 | 40.3 | 40.3 | 32.4 | 15.7 |  |  |  |
2018 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 15.8 | 14.9 | 16.1 | 16.8 | 16.4 | 14.6 |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,117 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 13.1 | 11.9 | 10.5 | 10.1 | 8.3 | 2.8 |  |  |  |
2018 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 18.1 | 17.7 | 18.1 | 17.8 | 20.3 | 25.8 |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.5 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,225 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 15.6 | 15.6 | 15.0 | 14.3 | 12.7 | 2.7 |  |  |  |
2018 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 9.2 | 8.6 | 10.9 | 11.1 | 13.3 | 12.9 |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,098 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 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 | 28.0 | 26.2 | 26.6 | 27.3 | 28.2 | 33.7 |  |  |  |
Total IBNR plus expected development on reported claims | $ 4.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,277 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 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 | 23.4 | 24.0 | 27.2 | 31.4 | 34.2 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,011 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 19.4 | 18.6 | 18.5 | 16.8 | 6.8 |  |  |  |  |
2019 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 30.1 | 25.7 | 18.7 | 19.6 | 21.8 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,368 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 25.2 | 18.3 | 7.5 | 7.0 | 4.9 |  |  |  |  |
2019 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 22.1 | 21.6 | 21.8 | 21.8 | 23.9 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,366 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 15.5 | 14.5 | 12.7 | 10.7 | 3.4 |  |  |  |  |
2019 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 11.4 | 10.6 | 12.4 | 13.7 | 14.8 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 2.6 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 954 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 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 | 24.9 | 23.4 | 23.3 | 26.6 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 5.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 971 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 15.2 | 12.2 | 7.8 | 5.8 | $ 3.3 |  |  |  |  |
2020 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 78.4 | 75.1 | 75.8 | 77.6 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 12.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 4,617 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 56.1 | 47.3 | 34.3 | 11.3 |  |  |  |  |  |
2020 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 19.9 | 19.0 | 23.2 | 24.2 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.7 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,994 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 18.3 | 13.2 | 10.7 | 5.3 |  |  |  |  |  |
2020 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 27.6 | 28.7 | 27.3 | 30.0 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.6 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,561 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 18.7 | 16.2 | 12.8 | 3.2 |  |  |  |  |  |
2020 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 9.2 | 10.9 | 12.1 | 13.5 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 4.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 605 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 3.3 | 2.0 | 1.0 | 0.5 |  |  |  |  |  |
2020 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 10.9 | 13.9 | 12.3 | 15.9 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 3.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 566 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 6.0 | 3.1 | 1.3 | $ 0.8 |  |  |  |  |  |
2021 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 167.3 | 155.5 | 171.8 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 5.7 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,465 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 131.3 | 87.1 | 30.9 |  |  |  |  |  |  |
2021 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 51.7 | 62.6 | 71.2 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 16.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,696 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 35.7 | 24.1 | 5.1 |  |  |  |  |  |  |
2021 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 67.7 | 69.8 | 86.8 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 9.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,461 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 38.5 | 24.5 | 6.3 |  |  |  |  |  |  |
2021 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 16.6 | 22.4 | 21.4 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 12.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 842 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 3.1 | 0.9 | 0.5 |  |  |  |  |  |  |
2021 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 5.5 | 7.0 | 10.5 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 3.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 282 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 1.9 | 1.7 | $ 0.5 |  |  |  |  |  |  |
2022 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 270.5 | 244.3 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 14.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 3,899 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 193.9 | 70.9 |  |  |  |  |  |  |  |
2022 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 176.6 | 181.1 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 97.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,407 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 62.1 | 16.0 |  |  |  |  |  |  |  |
2022 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 154.2 | 150.2 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 50.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,802 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 66.4 | 12.3 |  |  |  |  |  |  |  |
2022 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 38.1 | 33.0 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 34.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,237 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 1.6 | 0.4 |  |  |  |  |  |  |  |
2022 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 2.6 | 0.8 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 77 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 0.5 | $ 0.3 |  |  |  |  |  |  |  |
2023 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 214.2 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 156.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 2,963 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 20.1 |  |  |  |  |  |  |  |  |
2023 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 215.6 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 151.6 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,258 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 18.8 |  |  |  |  |  |  |  |  |
2023 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 197.8 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 154.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,539 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 10.6 |  |  |  |  |  |  |  |  |
2023 | Casualty-Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 61.0 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 57.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 1,065 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 0.9 |  |  |  |  |  |  |  |  |
2023 | Casualty-Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 2.7 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.6 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | claim | 40 |  |  |  |  |  |  |  |  |
Cumulative Paid Loss and LAE, Net of Reinsurance | $ 0.9 |  |  |  |  |  |  |  |  |

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