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Loss Reserves (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2026 | Mar. 31, 2025 | Dec. 31, 2025
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |
Increase (decrease) in loss reserves | $ 24,236 | $ 2,371 |
Losses incurred related to prior year notices | (31,229) | (49,906) |
Premium refund liability, expected claim payments | 11,800 |  | $ 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 | 20,000 |  |
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 | (26,965) | (46,497) |
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 | $ (4,264) | $ (3,409) |

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- Definition Amount of increase (decrease) in liability 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (a) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-28 + Details
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- Definition Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480046/944-40-55-7 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-3 + Details
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