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Loss Reserves - Narrative (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 USD ($) loan | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |
Minimum number of payments past due to be in default | loan | 2 |  |
Change in loss reserves (+/-) | $ (42,717) | $ (52,609) | $ (325,534)
Premium refund liability, expected claim payments | 12,500 | $ 21,100 |
$1,000 Increase/Decrease In Average Severity Reserve Factor |  |  |
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |
Change 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] |  |  |
Change in loss reserves (+/-) | $ 18,000 |  |

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- Definition The number of payments past due in order for such loans to be considered in default. + References No definition available. + Details
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- Definition The carrying amount for the estimate of premiums to be refunded on expected claim payments. + References No definition available. + Details
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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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