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v3.21.1

Third Party Reinsurance - Schedule of Reinsurance (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Earned premiums: |  |
Earned insurance premiums | $ 111.0 | $ 5.4
Losses and Loss Adjustment Expense [Abstract] |  |
Reinsurance recoverables on unpaid losses | 447.5 |
Reinsurance recoverables on paid losses | $ 1.5 |
Percent of reinsurance recoverables from insurers with excellent or higher credit quality | 90.00% |
Ark |  |
Written premiums: |  |
Direct | $ 404.5 |
Ceded | (62.1) |
Net written premiums | 342.4 |
Earned premiums: |  |
Direct | 162.6 |
Ceded | (58.0) |
Earned insurance premiums | 104.6 |
Losses and Loss Adjustment Expense [Abstract] |  |
Gross | 115.6 |
Ceded | (49.6) |
Net Losses and LAE | 66.0 |
Amount attributable to TPC Providers |  |
Losses and Loss Adjustment Expense [Abstract] |  |
Reinsurance recoverables on unpaid losses | 331.0 |
All Entities Except TCP Providers |  |
Losses and Loss Adjustment Expense [Abstract] |  |
Reinsurance recoverables on unpaid losses | $ 116.5 |

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