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Third-Party Reinsurance - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020
Reinsurance [Line Items] |  |
Total Reinsurance recoverables on unpaid losses | $ 428.9 |
Reinsurance recoverables on paid losses | 19.5 |
Ark |  |
Reinsurance [Line Items] |  |
Total Reinsurance recoverables on unpaid losses | 428.9 |
Reinsurance recoverables | $ 448.4 | $ 0.0
Ark | Third Point Re |  |
Reinsurance [Line Items] |  |
Annual crediting rate | 3.00% |
Decrease in investment | $ 31.7 |
Value of investment | 20.4 |
Amount attributable to TPC Providers |  |
Reinsurance [Line Items] |  |
Total Reinsurance recoverables on unpaid losses | $ 276.8 |

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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 http://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 http://asc.fasb.org/extlink&oid=123577603&loc=SL6953401-111524 + Details
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- Definition Amount before valuation allowance of reinsurance recoverables for losses reported to the ceding insurer but not yet paid, and for amounts expected based upon statistical projections and other measures of incurred losses and loss settlement expenses which have not yet been reported to the ceding insurer. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 20 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=99397103&loc=d3e6824-158387 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 310 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=99404803&loc=d3e21412-158489 + Details
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