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Statutory Information - Narrative (Details) $ in Millions | 1 Months Ended | 3 Months Ended
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Apr. 30, 2026 USD ($) | Mar. 31, 2026 jurisdiction
Statutory capital requirements [Abstract] |  |
Number of jurisdictions with risk-to-capital requirements (in jurisdictions) | jurisdiction |  | 16
Mortgage Guaranty Insurance Corporation |  |
Statutory capital requirements [Abstract] |  |
Percentage of statutory policyholders surplus used to determine maximum allowable dividends (as a percent) |  | 10.00%
Adjusted statutory net income measurement period (in years) |  | 3 years
Adjusted statutory net income dividend payment measurement period (in years) |  | 2 years
Mortgage Guaranty Insurance Corporation | Subsequent Event |  |
Statutory capital requirements [Abstract] |  |
Dividend paid to MGIC Investment Corp | $ | $ 400 |

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- Definition The number of jurisdictions that require a mortgage insurer to maintain a minimum amount of statutory capital relative to the risk in force (or a similar measure) in order for the mortgage insurer to continue to write new business. This is generally referred to as a risk-to-capital requirement. + References No definition available. + Details
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- Definition The percentage of statutory policyholders' surplus, as defined, as of the preceding calendar year end which is used in the determination of the maximum allowable dividends that the insurance subsidiaries may pay in any twelve-month period without regulatory approval by the Office of the Commissioner of Insurance of the State of Wisconsin. + References No definition available. + Details
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- Definition Statutory Accounting Practices, Statutory Amount Available For Dividend Payments Without Regulatory Approval, Measurement, Measurement Period + References No definition available. + Details
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- Definition Statutory Accounting Practices, Statutory Amount Available for Dividend Payments without Regulatory Approval, Measurement, Dividend Payment Period + References No definition available. + Details
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- References No definition available. + Details
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- Definition Amount of dividends paid subject to regulatory approval. + References No definition available. + Details
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- Details
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- Details
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