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Loss Reserves (Details) - USD ($) $ in Thousands | 6 Months Ended |
--- | --- | ---
Jun. 30, 2026 | Jun. 30, 2025 | Dec. 31, 2025
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |
Increase (decrease) in loss reserves | $ 17,117 | $ (10,508) |
Losses incurred related to prior year notices | (73,532) | (104,337) |
Premium refund liability, expected claim payments | 11,000 |  | $ 11,400
$1,000 Increase/Decrease In Average Severity Reserve Factor |  |  |
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |
Increase (decrease) in loss reserves | 7,000 |  |
One Percentage Point Increase/Decrease In Average Claim Rate Reserve Factor |  |  |
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |
Increase (decrease) in loss reserves | 19,000 |  |
Increase (decrease) in estimated claim rate on primary defaults |  |  |
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |
Losses incurred related to prior year notices | (65,125) | (98,645) |
Change in estimates related to severity on primary defaults, pool reserves, LAE reserves, reinsurance, and other |  |  |
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |
Losses incurred related to prior year notices | $ (8,407) | $ (5,692) |

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