Losses and LAE - Additional Information (Details) - Primary Mortgage Product - Mortgage Insurance revenues - Default	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
New primary defaults	36,568	31,555
Increase (decrease) in number of new primary default notices (in percent)	16.00%
Default to claim rate estimate, gross, for new defaults	8.00%	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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