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Reinsurance - Schedule of Ceded Premiums and Losses Related to Flood Operations (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Effects of Reinsurance [Line Items] |  |  |
Ceded premiums written | $ (717,013) | $ (614,926) | $ (527,248)
Ceded premiums earned | (684,955) | (583,977) | (537,884)
Ceded loss and loss expense incurred | (766,519) | (273,597) | (449,020)
NFIP |  |  |
Effects of Reinsurance [Line Items] |  |  |
Ceded premiums written | (356,957) | (305,609) | (259,246)
Ceded premiums earned | (328,811) | (279,087) | (274,100)
Ceded loss and loss expense incurred | $ (429,347) | $ (75,549) | $ (200,467)

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- Definition Amount of earned premiums ceded to other entities. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 235 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17(Column C)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477965/944-235-S99-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479032/944-605-50-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478832/944-605-45-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479032/944-605-50-1 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479032/944-605-50-1 + Details
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- Definition Amount of written premiums ceded to other entities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479032/944-605-50-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479032/944-605-50-1 + Details
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- Definition Amount of reduction of provision for policy benefits and costs incurred for policies ceded. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479838/944-20-50-3 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(5)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 + Details
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