Losses and LAE - Additional Information (Details) - Primary Mortgage Product - Mortgage Insurance revenues - Default	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024
Liability for Claims and Claims Adjustment Expense [Line Items]
New primary defaults	23,972	22,860
Increase (decrease) in number of new primary default notices (in percent)	5.00%
Default to claim rate estimate, gross, for new defaults	7.50%	8.00%

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.

No definition available.

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