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Loss Reserves (Details) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2018 USD ($) loan | Sep. 30, 2017 loan | Sep. 30, 2018 USD ($) loan | Sep. 30, 2017 USD ($) loan | Dec. 31, 2017 USD ($)
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |  |  |
Percentage of prior year delinquent inventory resolved (as a percent) |  |  | 65.00% | 59.00% |
Prior years | $ |  |  | $ 257,808 | $ 407,977 |
Premium refund liability, expected claim payments | $ | $ 44,000 |  | 44,000 |  | $ 61,000
Prior years | $ |  |  | $ (146,931) | $ (134,780) |
Primary Delinquent Inventory [Roll Forward] |  |  |  |  |
Delinquent inventory at the beginning of period (in loans) | loan | 36,037 | 41,317 | 46,556 | 50,282 |
New notices (in loans) | loan | 13,569 | 15,950 | 40,351 | 45,352 |
Cures (in loans) | loan | (14,197) | (13,546) | (47,620) | (45,382) |
Paids (including those charged to a deductible or captive) (in loans) | loan | (1,374) | (2,195) | (4,446) | (7,403) |
Rescissions and denials (in loans) | loan | (56) | (82) | (200) | (277) |
Other items removed from inventory (in loans) | loan | (581) | (209) | (1,243) | (1,337) |
Delinquent inventory at end of period (in loans) | loan | 33,398 | 41,235 | 33,398 | 41,235 |
Settlements for commutations of coverage, pools of nonperforming loans, and claims paying practices |  |  |  |  |
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |  |  |
Prior years | $ |  |  | $ 40,000 | $ 54,000 |
Decrease in estimated claim rate on primary defaults |  |  |  |  |
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |  |  |
Prior years | $ |  |  | (184,000) | (138,000) |
Increase in estimated severity on primary defaults |  |  |  |  |
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |  |  |
Prior years | $ |  |  | 22,000 | (2,000) |
Change in estimates related to pool reserves, LAE reserves and reinsurance |  |  |  |  |
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |  |  |
Prior years | $ |  |  | $ 15,000 | $ 5,000 |

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- Definition The percentage of the prior year default inventory resolved, which is used in the calculation of the change in the severity and claim rates. + 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 The number of loans in the primary default inventory. + References No definition available. + Details
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- Definition Deductions from the primary default inventory resulting from loans in default being brought current. + References No definition available. + Details
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