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Loss and Loss Adjustment Expense Reserves - Incurred Loss and Allocated LAE, Net of Reinsurance (Details) $ in Millions | Dec. 31, 2021 USD ($) basisPoint | Dec. 31, 2020 USD ($) | 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 ($) | Dec. 31, 2012 USD ($)
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Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 511.5 |  |  |  |  |  |  |  |  |
Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 259.8 |  |  |  |  |  |  |  |  |
Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 232.5 |  |  |  |  |  |  |  |  |
Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 82.2 |  |  |  |  |  |  |  |  |
Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 263.9 |  |  |  |  |  |  |  |  |
2012 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | 60.0 | $ 60.2 | $ 60.2 | $ 60.4 | $ 60.0 | $ 60.2 | $ 65.7 | $ 65.1 | $ 68.4 | $ 84.1
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.0 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 2,710 |  |  |  |  |  |  |  |  |
2012 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 32.1 | 32.0 | 32.0 | 32.6 | 32.8 | 33.6 | 42.8 | 46.0 | 55.1 | 64.7
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.1 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 2,428 |  |  |  |  |  |  |  |  |
2012 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 26.8 | 26.8 | 26.6 | 26.3 | 25.8 | 26.7 | 30.8 | 31.8 | 36.1 | 43.1
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 2.1 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 887 |  |  |  |  |  |  |  |  |
2012 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 11.1 | 11.3 | 11.0 | 11.0 | 9.9 | 10.1 | 16.2 | 17.7 | 21.1 | 22.6
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.8 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,016 |  |  |  |  |  |  |  |  |
2012 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 23.1 | 22.7 | 22.8 | 22.3 | 21.7 | 22.3 | 34.4 | 37.8 | 44.6 | $ 44.3
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ (0.2) |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,430 |  |  |  |  |  |  |  |  |
2013 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 61.6 | 61.6 | 61.6 | 61.7 | 61.6 | 62.1 | 66.6 | 66.9 | 74.6 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.4 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 2,586 |  |  |  |  |  |  |  |  |
2013 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 29.9 | 29.6 | 29.7 | 29.9 | 31.0 | 31.6 | 41.9 | 50.8 | 64.9 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ (0.2) |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 2,641 |  |  |  |  |  |  |  |  |
2013 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 17.3 | 17.3 | 16.9 | 17.1 | 16.9 | 17.5 | 25.6 | 34.9 | 48.6 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1.3 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,122 |  |  |  |  |  |  |  |  |
2013 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 8.9 | 9.0 | 8.8 | 8.9 | 8.1 | 8.3 | 15.0 | 18.8 | 23.2 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1.3 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,134 |  |  |  |  |  |  |  |  |
2013 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 49.9 | 49.8 | 49.8 | 49.8 | 47.0 | 49.2 | 70.1 | 75.8 | $ 65.7 |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 3.1 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,810 |  |  |  |  |  |  |  |  |
2014 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 28.5 | 28.5 | 28.5 | 28.6 | 28.6 | 29.4 | 31.3 | 34.8 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.0 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 2,963 |  |  |  |  |  |  |  |  |
2014 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 14.4 | 14.4 | 14.3 | 14.7 | 16.2 | 17.4 | 27.2 | 41.3 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.5 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 2,581 |  |  |  |  |  |  |  |  |
2014 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 43.5 | 43.5 | 42.9 | 41.5 | 41.3 | 41.9 | 51.1 | 51.1 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ (0.3) |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,409 |  |  |  |  |  |  |  |  |
2014 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 7.7 | 7.8 | 7.8 | 8.0 | 7.0 | 7.5 | 13.8 | 17.1 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1.2 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,359 |  |  |  |  |  |  |  |  |
2014 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 55.0 | 56.0 | 55.6 | 55.9 | 46.0 | 46.8 | 67.5 | $ 46.9 |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1.9 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,932 |  |  |  |  |  |  |  |  |
2015 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 15.9 | 15.9 | 15.9 | 16.0 | 16.2 | 17.4 | 19.8 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.4 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 2,884 |  |  |  |  |  |  |  |  |
2015 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 12.2 | 12.0 | 12.0 | 12.7 | 13.6 | 15.4 | 25.3 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.2 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 3,390 |  |  |  |  |  |  |  |  |
2015 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 10.8 | 10.7 | 10.6 | 10.1 | 10.4 | 13.0 | 21.3 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1.7 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,876 |  |  |  |  |  |  |  |  |
2015 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 6.2 | 6.4 | 6.5 | 7.0 | 6.0 | 7.7 | 12.3 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.6 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,247 |  |  |  |  |  |  |  |  |
2015 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 32.0 | 33.2 | 33.0 | 35.7 | 26.4 | 23.9 | $ 26.9 |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1.4 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 2,009 |  |  |  |  |  |  |  |  |
2016 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 18.0 | 17.9 | 18.0 | 17.9 | 16.9 | 21.7 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ (0.3) |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 3,478 |  |  |  |  |  |  |  |  |
2016 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 15.1 | 14.9 | 15.1 | 16.0 | 18.1 | 22.3 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.7 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 4,117 |  |  |  |  |  |  |  |  |
2016 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 9.3 | 9.0 | 9.2 | 8.7 | 11.7 | 15.9 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ (1.3) |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,941 |  |  |  |  |  |  |  |  |
2016 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 6.9 | 7.0 | 6.6 | 6.3 | 5.0 | 5.7 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.1 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,483 |  |  |  |  |  |  |  |  |
2016 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 34.1 | 35.3 | 35.4 | 38.8 | 25.3 | $ 19.1 |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 3.8 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 2,141 |  |  |  |  |  |  |  |  |
2017 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 36.0 | 36.7 | 37.4 | 29.9 | 22.6 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 3.6 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 4,610 |  |  |  |  |  |  |  |  |
2017 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 16.5 | 16.4 | 16.9 | 18.6 | 23.9 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1.1 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 4,470 |  |  |  |  |  |  |  |  |
2017 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 10.6 | 10.5 | 10.9 | 11.9 | 16.0 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1.5 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 2,179 |  |  |  |  |  |  |  |  |
2017 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 5.9 | 6.2 | 7.2 | 7.8 | 7.4 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.7 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,489 |  |  |  |  |  |  |  |  |
2017 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 26.7 | 28.0 | 26.7 | 27.2 | $ 17.4 |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 2.5 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,597 |  |  |  |  |  |  |  |  |
2018 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 44.5 | 46.3 | 44.2 | 37.5 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1.5 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 4,270 |  |  |  |  |  |  |  |  |
2018 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 17.0 | 16.7 | 18.9 | 24.5 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.5 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 3,487 |  |  |  |  |  |  |  |  |
2018 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 13.7 | 14.8 | 13.9 | 12.1 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 2.4 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 2,090 |  |  |  |  |  |  |  |  |
2018 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 7.1 | 7.3 | 9.0 | 8.7 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.9 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 961 |  |  |  |  |  |  |  |  |
2018 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 20.0 | 20.2 | 18.2 | $ 13.5 |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 2.9 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,265 |  |  |  |  |  |  |  |  |
2019 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 23.4 | 27.8 | 30.4 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 2.1 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 4,073 |  |  |  |  |  |  |  |  |
2019 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 17.2 | 17.3 | 19.3 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.6 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 2,562 |  |  |  |  |  |  |  |  |
2019 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 13.5 | 14.6 | 16.6 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 2.8 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 2,315 |  |  |  |  |  |  |  |  |
2019 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 6.3 | 7.4 | 8.0 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 1.7 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 742 |  |  |  |  |  |  |  |  |
2019 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 15.4 | 14.3 | $ 10.8 |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 3.7 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 961 |  |  |  |  |  |  |  |  |
2020 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 61.5 | 62.9 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 15.2 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 4,532 |  |  |  |  |  |  |  |  |
2020 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 21.7 | 24.4 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 2.9 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,668 |  |  |  |  |  |  |  |  |
2020 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 19.7 | 20.7 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 6.2 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,925 |  |  |  |  |  |  |  |  |
2020 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 6.2 | 7.6 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 3.9 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 420 |  |  |  |  |  |  |  |  |
2020 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 6.0 | $ 4.2 |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 3.6 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 552 |  |  |  |  |  |  |  |  |
2021 | Property and Accident & Health |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 162.1 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 70.8 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 2,860 |  |  |  |  |  |  |  |  |
2021 | Marine & Energy |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 83.7 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 69.9 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,091 |  |  |  |  |  |  |  |  |
2021 | Specialty |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 67.3 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 57.4 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 1,341 |  |  |  |  |  |  |  |  |
2021 | Casualty - Active |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 15.9 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 14.2 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 452 |  |  |  |  |  |  |  |  |
2021 | Casualty - Runoff |  |  |  |  |  |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Loss and LAE, Net of Reinsurance | $ 1.7 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net | $ 0.4 |  |  |  |  |  |  |  |  |
Short-duration Insurance Contract, Cumulative Number of Reported Claims | basisPoint | 260 |  |  |  |  |  |  |  |  |

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