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Reinsurance - Schedule of Total Reinsurance Balances Segregated By Reinsurer (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | ---
Ceded Credit Risk [Line Items] |  |  |
Total reinsurance recoverable, net | $ 1,061,145 | $ 656,825 |
Total prepaid reinsurance premiums | 235,378 | 203,320 |
Reinsurance Balances | 1,296,523 | 860,145 |
Less: collateral | (93,842) | (126,418) |
Less: ACL | (2,000) | (1,700) | $ (1,600)
Total federal and state pools |  |  |
Ceded Credit Risk [Line Items] |  |  |
Reinsurance Balances | $ 518,203 | $ 251,767 |
% of Reinsurance Balance | 39.00% | 29.00% |
NFIP |  |  |
Ceded Credit Risk [Line Items] |  |  |
Reinsurance Balances | $ 471,696 | $ 203,273 |
% of Reinsurance Balance | 36.00% | 24.00% |
New Jersey Unsatisfied Claim Judgment Fund |  |  |
Ceded Credit Risk [Line Items] |  |  |
Reinsurance Balances | $ 44,089 | $ 46,715 |
% of Reinsurance Balance | 3.00% | 5.00% |
Other than federal and state pools |  |  |
Ceded Credit Risk [Line Items] |  |  |
Reinsurance Balances | $ 2,418 | $ 1,779 |
% of Reinsurance Balance | 0.00% | 0.00% |
Remaining reinsurance balance |  |  |
Ceded Credit Risk [Line Items] |  |  |
Reinsurance Balances | $ 780,320 | $ 610,078 |
% of Reinsurance Balance | 61.00% | 71.00% |
Remaining reinsurance balance | $ 778,320 | $ 608,378 |
Reinsurers, net of ACL | 778,320 | 608,378 |
Hannover Ruck SE (AM Best rated "A+") |  |  |
Ceded Credit Risk [Line Items] |  |  |
Reinsurance Balances | $ 198,966 | $ 135,564 |
% of Reinsurance Balance | 15.00% | 16.00% |
Munich Reinsurance America Inc. (AM Best rated "A+") |  |  |
Ceded Credit Risk [Line Items] |  |  |
Reinsurance Balances | $ 151,516 | $ 132,831 |
% of Reinsurance Balance | 12.00% | 15.00% |
AXIS Reinsurance Company (AM Best rated "A") |  |  |
Ceded Credit Risk [Line Items] |  |  |
Reinsurance Balances | $ 91,862 | $ 76,286 |
% of Reinsurance Balance | 7.00% | 9.00% |
Endurance Assurance Corporation (AM Best rated “A+”) |  |  |
Ceded Credit Risk [Line Items] |  |  |
Reinsurance Balances | $ 40,717 | $ 27,246 |
% of Reinsurance Balance | 3.00% | 3.00% |
Ace Property & Casualty Insurance Company (AM Best rated “A++”) |  |  |
Ceded Credit Risk [Line Items] |  |  |
Reinsurance Balances | $ 30,166 | $ 13,602 |
% of Reinsurance Balance | 2.00% | 2.00% |
All other reinsurers |  |  |
Ceded Credit Risk [Line Items] |  |  |
Reinsurance Balances | $ 267,093 | $ 224,549 |
% of Reinsurance Balance | 22.00% | 26.00% |
Reinsurers, net of collateral |  |  |
Ceded Credit Risk [Line Items] |  |  |
Reinsurance Balances | $ 684,478 | $ 481,960 |

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- Definition This element represents the amount collateralized by the entity's reinsurers. The amount includes letters of credit, trust funds, and funds withheld. + References No definition available. + Details
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- Definition This element represents the percentage of the total net unsecured reinsurance balance. + References No definition available. + Details
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- Definition This element represents the known and estimated amount of reinsurance recoverables and the unexpired portion of premiums ceded on policies in force, less all federal and state pools, as of the balance sheet date. + References No definition available. + Details
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- Definition This element represents the known and estimated amount of reinsurance recoverables and the unexpired portion of premiums ceded on policies in force, less all federal and state pools, as of the balance sheet date. + References No definition available. + Details
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- Definition The unexpired portion of premiums ceded on policies in force as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 825 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477351/944-825-50-1B Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 340 -Name Accounting Standards Codification -Section 25 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479510/944-340-25-1 + Details
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- Definition Amount, after valuation allowance, recoverable under reinsurance contracts including premium paid 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/2009/role/commonPracticeRef -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 2: http://www.xbrl.org/2009/role/commonPracticeRef -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 3: http://www.xbrl.org/2009/role/commonPracticeRef -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 + Details
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- Definition Amount, after 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, policy benefits and policy reserves. Excludes premiums paid under reinsurance contracts. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -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/2009/role/commonPracticeRef -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 3: http://www.xbrl.org/2009/role/commonPracticeRef -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 4: http://www.xbrl.org/2009/role/commonPracticeRef -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 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 825 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477351/944-825-50-1B + Details
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