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Loss and Loss Adjustment Expense Reserves - Incurred Loss and Allocated LAE, Net of Reinsurance (Details) - Ark $ in Millions | Dec. 31, 2022 USD ($) basisPoint | Dec. 31, 2021 USD ($) | 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 ($) | Dec. 31, 2013 USD ($)
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Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 667.0 |  |  |  |  |  |  |  |  |
Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 356.4 |  |  |  |  |  |  |  |  |
Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 369.9 |  |  |  |  |  |  |  |  |
Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 109.5 |  |  |  |  |  |  |  |  |
Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 256.2 |  |  |  |  |  |  |  |  |
2013 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 59.3 | $ 59.3 | $ 59.3 | $ 59.4 | $ 59.5 | $ 59.6 | $ 60.1 | $ 60.3 | $ 60.4 | $ 67.8
Total IBNR plus expected development on reported claims | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 2,530 |  |  |  |  |  |  |  |  |
2013 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 29.3 | 29.4 | 29.3 | 29.5 | 29.6 | 30.8 | 31.0 | 32.3 | 41.7 | 55.4
Total IBNR plus expected development on reported claims | $ (0.2) |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 2,638 |  |  |  |  |  |  |  |  |
2013 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 15.8 | 15.7 | 15.7 | 15.5 | 15.8 | 15.9 | 16.2 | 17.6 | 28.5 | 47.0
Total IBNR plus expected development on reported claims | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,042 |  |  |  |  |  |  |  |  |
2013 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 7.8 | 7.8 | 7.8 | 7.7 | 8.1 | 8.0 | 8.0 | 8.5 | 13.0 | 18.2
Total IBNR plus expected development on reported claims | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,144 |  |  |  |  |  |  |  |  |
2013 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 47.5 | 47.5 | 47.5 | 47.7 | 47.3 | 47.6 | 49.0 | 47.7 | 51.4 | $ 47.7
Total IBNR plus expected development on reported claims | $ 1.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,798 |  |  |  |  |  |  |  |  |
2014 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 28.2 | 28.2 | 28.2 | 28.2 | 28.1 | 28.3 | 29.0 | 29.1 | 32.2 |
Total IBNR plus expected development on reported claims | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 2,919 |  |  |  |  |  |  |  |  |
2014 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 13.7 | 13.6 | 13.9 | 13.6 | 14.0 | 16.1 | 17.0 | 19.9 | 34.1 |
Total IBNR plus expected development on reported claims | $ (0.2) |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 2,572 |  |  |  |  |  |  |  |  |
2014 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 43.1 | 43.3 | 43.4 | 43.3 | 40.8 | 40.4 | 40.8 | 43.8 | 45.5 |
Total IBNR plus expected development on reported claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,357 |  |  |  |  |  |  |  |  |
2014 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 7.1 | 6.9 | 7.1 | 7.0 | 7.4 | 7.5 | 7.7 | 8.7 | 12.6 |
Total IBNR plus expected development on reported claims | $ 0.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,385 |  |  |  |  |  |  |  |  |
2014 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 55.6 | 55.8 | 56.0 | 56.0 | 54.5 | 50.9 | 47.8 | 45.3 | $ 45.8 |
Total IBNR plus expected development on reported claims | $ 1.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,941 |  |  |  |  |  |  |  |  |
2015 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 15.4 | 15.5 | 15.7 | 15.7 | 15.9 | 16.9 | 17.9 | 18.8 |  |
Total IBNR plus expected development on reported claims | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 2,826 |  |  |  |  |  |  |  |  |
2015 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 12.2 | 12.0 | 12.1 | 12.0 | 12.6 | 15.4 | 16.7 | 21.0 |  |
Total IBNR plus expected development on reported claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 3,238 |  |  |  |  |  |  |  |  |
2015 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 7.8 | 10.1 | 10.1 | 9.9 | 9.6 | 11.2 | 13.6 | 16.2 |  |
Total IBNR plus expected development on reported claims | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,840 |  |  |  |  |  |  |  |  |
2015 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 6.5 | 6.3 | 6.4 | 6.6 | 7.3 | 7.4 | 9.0 | 8.8 |  |
Total IBNR plus expected development on reported claims | $ 0.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,280 |  |  |  |  |  |  |  |  |
2015 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 36.6 | 34.1 | 34.8 | 33.8 | 34.0 | 30.6 | 29.4 | $ 33.8 |  |
Total IBNR plus expected development on reported claims | $ 1.6 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,995 |  |  |  |  |  |  |  |  |
2016 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 18.2 | 18.3 | 18.1 | 18.1 | 17.9 | 17.2 | 21.9 |  |  |
Total IBNR plus expected development on reported claims | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 3,419 |  |  |  |  |  |  |  |  |
2016 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 13.8 | 14.5 | 14.0 | 14.3 | 15.4 | 19.2 | 23.1 |  |  |
Total IBNR plus expected development on reported claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 3,764 |  |  |  |  |  |  |  |  |
2016 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 8.8 | 11.6 | 11.7 | 11.1 | 10.8 | 14.1 | 18.1 |  |  |
Total IBNR plus expected development on reported claims | $ 0.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,927 |  |  |  |  |  |  |  |  |
2016 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 8.1 | 8.0 | 7.9 | 7.8 | 7.8 | 7.1 | 7.6 |  |  |
Total IBNR plus expected development on reported claims | $ 0.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,528 |  |  |  |  |  |  |  |  |
2016 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 33.8 | 34.6 | 34.9 | 34.7 | 36.5 | 28.3 | $ 28.6 |  |  |
Total IBNR plus expected development on reported claims | $ 1.7 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 2,150 |  |  |  |  |  |  |  |  |
2017 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 36.0 | 36.5 | 37.9 | 38.9 | 31.4 | 24.6 |  |  |  |
Total IBNR plus expected development on reported claims | $ 5.7 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 4,599 |  |  |  |  |  |  |  |  |
2017 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 15.0 | 15.9 | 16.2 | 16.8 | 18.6 | 25.3 |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 4,117 |  |  |  |  |  |  |  |  |
2017 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 10.0 | 11.0 | 10.8 | 11.3 | 12.2 | 17.3 |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 2,187 |  |  |  |  |  |  |  |  |
2017 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 8.4 | 7.0 | 7.3 | 8.7 | 9.6 | 9.5 |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,580 |  |  |  |  |  |  |  |  |
2017 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 26.7 | 28.4 | 28.9 | 28.2 | 30.8 | $ 27.4 |  |  |  |
Total IBNR plus expected development on reported claims | $ 2.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,599 |  |  |  |  |  |  |  |  |
2018 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 44.2 | 44.1 | 46.4 | 44.5 | 38.1 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 4,254 |  |  |  |  |  |  |  |  |
2018 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 16.6 | 17.0 | 16.6 | 19.1 | 24.6 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 3,205 |  |  |  |  |  |  |  |  |
2018 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 13.5 | 14.7 | 15.4 | 14.9 | 13.2 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.7 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 2,110 |  |  |  |  |  |  |  |  |
2018 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 6.8 | 9.0 | 9.2 | 11.5 | 11.0 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,036 |  |  |  |  |  |  |  |  |
2018 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 21.9 | 22.3 | 23.0 | 23.9 | $ 29.4 |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 3.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,267 |  |  |  |  |  |  |  |  |
2019 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 21.5 | 24.7 | 28.9 | 31.6 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.7 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 3,999 |  |  |  |  |  |  |  |  |
2019 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 18.3 | 18.6 | 18.6 | 20.7 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.6 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 2,331 |  |  |  |  |  |  |  |  |
2019 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 22.4 | 15.4 | 16.3 | 18.5 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 2,347 |  |  |  |  |  |  |  |  |
2019 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 7.3 | 9.1 | 10.4 | 11.6 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 2.4 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 834 |  |  |  |  |  |  |  |  |
2019 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 19.4 | 18.0 | 17.8 | $ 21.1 |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 5.0 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 961 |  |  |  |  |  |  |  |  |
2020 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 62.9 | 63.3 | 65.2 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 7.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 4,551 |  |  |  |  |  |  |  |  |
2020 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 23.2 | 21.7 | 24.4 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 1.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,529 |  |  |  |  |  |  |  |  |
2020 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 16.3 | 20.5 | 21.4 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 2.5 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,985 |  |  |  |  |  |  |  |  |
2020 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 7.1 | 8.3 | 9.7 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 4.2 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 524 |  |  |  |  |  |  |  |  |
2020 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 9.3 | 7.6 | $ 11.3 |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 3.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 558 |  |  |  |  |  |  |  |  |
2021 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 146.8 | 163.0 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 10.6 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 3,318 |  |  |  |  |  |  |  |  |
2021 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 66.1 | 83.0 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 24.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,356 |  |  |  |  |  |  |  |  |
2021 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 59.4 | 67.6 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 33.9 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,644 |  |  |  |  |  |  |  |  |
2021 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 18.4 | 17.4 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 16.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 674 |  |  |  |  |  |  |  |  |
2021 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 4.8 | $ 8.2 |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 2.7 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 277 |  |  |  |  |  |  |  |  |
2022 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 234.5 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 90.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 2,899 |  |  |  |  |  |  |  |  |
2022 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 148.2 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 99.5 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 1,188 |  |  |  |  |  |  |  |  |
2022 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 172.8 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 125.3 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 985 |  |  |  |  |  |  |  |  |
2022 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 32.0 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 28.8 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 832 |  |  |  |  |  |  |  |  |
2022 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 0.6 |  |  |  |  |  |  |  |  |
Total IBNR plus expected development on reported claims | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative number of reported claims | basisPoint | 76 |  |  |  |  |  |  |  |  |

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