Description of Business - Additional Information (Details) $ in Millions |
1 Months Ended | 3 Months Ended | 12 Months Ended |
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Sep. 30, 2025
USD ($)
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Mar. 31, 2026
USD ($)
Segment
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Dec. 31, 2025
USD ($)
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| Business Overview [Abstract] | |||
| Number of reportable business segments | Segment | 2 | ||
| Proceeds from intercompany notes borrowings | $ 600 | $ 600 | |
| Debt instrument term | 10 years | 10 years | |
| Acquisition related costs | $ 22 | 10 | |
| Inigo Limited | |||
| Business Overview [Abstract] | |||
| Payments to acquire businesses gross | $ 1,670 | ||
| Mortgage Insurance revenues | |||
| Business Overview [Abstract] | |||
| Down payment purchase price (percent) | 20.00% | ||
| Equity in home (percent) | 20.00% | ||
| Direct primary mortgage insurance in force | $ 281,700 | 282,500 | |
| Direct primary mortgage insurance risk in force | $ 74,700 | $ 74,700 |
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- Definition Business Overview [Abstract] No definition available.
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- Definition This element represents the maximum down payment percentage on a home's purchase price that is used to measure the need for private mortgage insurance. No definition available.
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- Definition This element represents the maximum equity-ownership percentage on a home's value that is used to measure the need for private mortgage insurance for refinancings. No definition available.
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- Definition Proceeds from intercompany notes borrowings. No definition available.
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- Definition Risk In Force, Ceded Amount No definition available.
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- Definition Amount of expense for acquisition-related cost incurred to effect business combination. Includes, but is not limited to, finder's fee; advisory, legal, accounting, valuation, and other professional and consulting fees; and general administrative cost, including cost of maintaining internal acquisition department. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. No definition available.
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- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of participating insurance in force. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Details
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- Details
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