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Insurance - Summary of Percentage Ceded to Reinsurers and Reinsurance Recoverable and Rating Levels (Details) $ in Thousands | Mar. 31, 2026 USD ($) | Dec. 31, 2025 USD ($) | Mar. 31, 2025 USD ($)
--- | --- | --- | ---
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items] |  |  |
Ceded Loss And Loss Expenses Paid Not Yet Recovered |  |  | $ 56,190
Reinsurance Recoverable, Allowance for Credit Loss | $ 100 | $ 100 |
Reinsurance Recoverables, Gross | 469,859 |  |
Unsecured Reinsurance Recoverables | 327,935 |  |
Reinsurance Recoverable, Gross, All Other | 225,084 |  |
Unsecured Reinsurance Recoverable, All Other | 112,773 |  |
Letters of Credit Outstanding, Amount | $ 80,351 |  |
Number of Reinsurers Covering Majority | 5 |  |
Percentage of Ceded Reinsurance Recoverable Represented by Top Three | 52.10% |  |
Uncollateralized Credit Exposure Supoorted by Unlimited Uncapped Indemnity | $ 21,273 | 23,530 |
Deferred Ceded Premiums And Reinsurance Recoverables | 615,279 |  |
Reinsurance Recoverable Credit Exposure | 327,935 | $ 311,795 |
QBE Insurance Corporation | Property and Casualty, Commercial Insurance | Standard & Poor's, A Rating |  |  |
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items] |  |  |
Reinsurance Recoverables, Gross | 17,989 |  |
Unsecured Reinsurance Recoverables | 17,989 |  |
Assured Guaranty Re Ltd | Financial Guarantee | Standard & Poor's, A+ Rating |  |  |
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items] |  |  |
Reinsurance Recoverables, Gross | 65,092 |  |
Unsecured Reinsurance Recoverables | 63,828 |  |
General Reinsurance Company | Property and Casualty, Commercial Insurance | Standard Poors A Plus Plus Rating |  |  |
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items] |  |  |
Reinsurance Recoverables, Gross | 128,406 |  |
Unsecured Reinsurance Recoverables | 100,301 |  |
Swiss Reinsurance America Corporation | Financial Guarantee | Standard & Poor's, A+ Rating |  |  |
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items] |  |  |
Reinsurance Recoverables, Gross | 15,512 |  |
Unsecured Reinsurance Recoverables | 14,788 |  |
Swiss Reinsurance America Corporation | Financial Guarantee | Standard & Poors, No Rating |  |  |
Summary of Ceded Par and Net Unsecured Reinsurance Recoverable [Line Items] |  |  |
Reinsurance Recoverables, Gross | 17,776 |  |
Unsecured Reinsurance Recoverables | $ 18,256 |  |

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- Definition Includes the unexpired portion of financial guarantee premiums ceded on policies as of the balance sheet date and reinsurance recoverables on claims or claim adjustment expense paid by the ceding insurer. + References No definition available. + Details
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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 -Topic 944 -SubTopic 310 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477363/944-310-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 310 -Name Accounting Standards Codification -Section 45 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477409/944-310-45-6 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 55 -Paragraph 14 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477548/944-605-55-14 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477548/944-605-55-12 Reference 5: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-7A Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479838/944-20-50-5 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(6)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 310 -Name Accounting Standards Codification -Section 45 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477409/944-310-45-5 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 14 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-14 + Details
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