Loss reserves - Summary of Liability For Unpaid Claims And Claim Adjustment Expenses (Details) - USD ($) $ in Thousands |
Jun. 30, 2026 |
Dec. 31, 2025 |
Jun. 30, 2025 |
Dec. 31, 2024 |
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| Effects of Reinsurance [Line Items] | ||||
| Loss reserves | $ 598,686 | $ 572,470 | ||
| Domestic mortgage insurance | ||||
| Effects of Reinsurance [Line Items] | ||||
| Loss reserves | 591,760 | 566,809 | $ 546,310 | $ 520,032 |
| Other reserves | ||||
| Effects of Reinsurance [Line Items] | ||||
| Loss reserves | $ 6,926 | $ 5,661 |
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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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The amount needed to reflect the estimated ultimate cost of settling claims relating to insured events that have occurred on or before the balance sheet date, whether or not reported to the insurer at that date. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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