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SCHEDULE III - SUPPLEMENTARY INSURANCE INFORMATION (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
HG Global/BAM |  |  |
SUPPLEMENTARY INSURANCE INFORMATION |  |  |
Deferred Acquisition Costs | $ 40.1 | $ 36.0 | $ 33.1
Future Policy Benefits, Losses, Claims and Loss Expenses | 0.0 | 0.0 | 0.0
Unearned Premiums | 325.8 | 298.3 | 266.3
Other Policy Claims and Benefits Payable | 0.0 | 0.0 | 0.0
Premiums Earned | 31.2 | 33.3 | 26.9
Net Investment Income | 31.7 | 21.5 | 17.5
Benefits, Claims, Losses and Settlement Expenses | 0.0 | 0.0 | 0.0
Amortization of Deferred Acquisition Costs | 8.6 | 11.2 | 8.3
Other Operating Expenses | 0.4 | 0.4 | 0.4
Premiums Written | 58.6 | 65.1 | 55.8
Ark/WM Outrigger |  |  |
SUPPLEMENTARY INSURANCE INFORMATION |  |  |
Deferred Acquisition Costs | 145.3 | 127.2 | 100.8
Future Policy Benefits, Losses, Claims and Loss Expenses | 1,605.1 | 1,296.5 | 894.7
Unearned Premiums | 743.6 | 623.2 | 495.9
Other Policy Claims and Benefits Payable | 0.0 | 0.0 | 0.0
Premiums Earned | 1,409.7 | 1,043.4 | 637.3
Net Investment Income | 61.4 | 16.3 | 2.9
Benefits, Claims, Losses and Settlement Expenses | 726.8 | 536.4 | 314.8
Amortization of Deferred Acquisition Costs | 273.1 | 238.3 | 111.3
Other Operating Expenses | 113.6 | 78.7 | 64.6
Premiums Written | $ 1,520.9 | $ 1,195.2 | $ 859.1

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