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Reinsurance - Additional Information (Details) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2025 | Dec. 31, 2024
Radian Guaranty |  |
Ceded Credit Risk [Line Items] |  |
Funds held under reinsurance agreements, asset | $ 304 | $ 283
Mortgage Insurance revenues |  |
Ceded Credit Risk [Line Items] |  |
Direct primary mortgage insurance risk in force | $ 74,000 | $ 72,100
Maximum | Mortgage Insurance revenues | Radian Guaranty |  |
Ceded Credit Risk [Line Items] |  |
Reinsurance retention policy, term of coverage, period | 12 years 6 months |
Maximum | Excess-of-Loss Program | Radian Guaranty |  |
Ceded Credit Risk [Line Items] |  |
Right to termination on or after option call date, period after issuance of insurance-linked notes | 7 years |
Minimum | Mortgage Insurance revenues | Radian Guaranty |  |
Ceded Credit Risk [Line Items] |  |
Reinsurance retention policy, term of coverage, period | 10 years |
Minimum | Excess-of-Loss Program | Radian Guaranty |  |
Ceded Credit Risk [Line Items] |  |
Right to termination on or after option call date, period after issuance of insurance-linked notes | 5 years |

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- Definition Reinsurance Agreement, Right To Terminate, Option Call Date, Period After Issuance Of Insurance-Linked Notes + References No definition available. + Details
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- Definition Reinsurance Retention Policy, Term Of Coverage, Period + References No definition available. + Details
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- Definition Risk In Force, Ceded Amount + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + 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 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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- Definition Amount of the reinsurer's funds held on its behalf by the ceding insurer, including funds held in trust, under reinsurance treaties or contracts with the assuming insurer as security for the payment of the obligations thereunder. + References Reference 1: 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)(10)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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- Details
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- Details
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- Details
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- Details
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- Details
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