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Third-Party Reinsurance - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2021 | Sep. 30, 2022 | Sep. 30, 2021
Reinsurance [Line Items] |  |  |
Reinsurance recoverables on unpaid losses |  | $ 521.4 | $ 457.5
Reinsurance recoverables on paid losses |  | 29.5 | 8.1
TPC Providers |  |  |
Reinsurance [Line Items] |  |  |
Reinsurance recoverables |  |  | 299.9
Ark |  |  |
Reinsurance [Line Items] |  |  |
Reinsurance recoverables | $ 448.4 | 550.9 | 465.6
Ark | TPC Providers |  |  |
Reinsurance [Line Items] |  |  |
Reinsurance recoverables |  | 168.0 | $ 299.9
Ark | Third Point Re |  |  |
Reinsurance [Line Items] |  |  |
Annual crediting rate | 3.00% |  |
Decrease in investment | $ 31.7 |  |
Carrying value of investment |  | $ 20.3 |

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- Definition Amount before valuation allowance recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 14 -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919253-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7A -URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953401-111524 + Details
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