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Loss Reserves - Delinquent Items (Details) - loan | Sep. 30, 2018 | Jun. 30, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Dec. 31, 2016
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Aging of the Primary Delinquent Inventory [Abstract] |  |  |  |  |  |
3 months or less (in loans) | 9,484 |  | 17,119 | 11,331 |  |
3 months or less (as a percent) | 28.00% |  | 37.00% | 27.00% |  |
4 - 11 months (in loans) | 9,564 |  | 12,050 | 11,092 |  |
4 - 11 months (as a percent) | 29.00% |  | 26.00% | 27.00% |  |
12 months or more (in loans) | 14,350 |  | 17,387 | 18,812 |  |
12 months or more (as a percent) | 43.00% |  | 37.00% | 46.00% |  |
Total primary delinquent inventory (in loans) | 33,398 | 36,037 | 46,556 | 41,235 | 41,317 | 50,282
Total primary delinquent inventory (as a percent) | 100.00% |  | 100.00% | 100.00% |  |
Primary claims received inventory included in ending delinquent inventory (in loans) | 766 |  | 954 | 1,063 |  |
Primary claims received inventory included in ending delinquent inventory (as a percent) | 2.00% |  | 2.00% | 3.00% |  |
Percent of 12 months or more delinquent inventory, delinquent for more than 36 months (as a percent) | 39.00% |  | 45.00% | 45.00% |  |
Number of payments delinquent [Abstract] |  |  |  |  |  |
3 payments or less (in loans) | 14,813 |  | 21,678 | 16,916 |  |
3 payments or less (as a percent) | 44.00% |  | 46.00% | 41.00% |  |
4 - 11 payments (in loans) | 9,156 |  | 12,446 | 10,583 |  |
4 - 11 payments (as a percent) | 28.00% |  | 27.00% | 26.00% |  |
12 payments or more (in loans) | 9,429 |  | 12,432 | 13,736 |  |
12 payments or more (as a percent) | 28.00% |  | 27.00% | 33.00% |  |
Total primary delinquent inventory (in loans) | 33,398 | 36,037 | 46,556 | 41,235 | 41,317 | 50,282
Total primary delinquent inventory (as a percent) | 100.00% |  | 100.00% | 100.00% |  |
Percent of 12 payments or more delinquent inventory, 36 payments or more delinquent (as a percent) | 39.00% |  | 43.00% | 43.00% |  |
Pool insurance delinquent inventory (in loans) | 1,032 |  | 1,309 | 1,426 |  |

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- References No definition available. + Details
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X
- Definition The number of loans in the primary default inventory that have been delinquent for twelve payments or more. + References No definition available. + Details
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- Definition The percentage of loans in the primary default inventory that have been delinquent for twelve payments or more. + References No definition available. + Details
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- Definition The number of loans in the primary default inventory that have been delinquent for three payments or less. + References No definition available. + Details
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- Definition The percentage of loans in the primary default inventory that have been delinquent for three payments or less. + References No definition available. + Details
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Data Type: | num:percentItemType
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X
- Definition The number of loans in the primary default inventory that have been delinquent for at least four payments but no more than eleven payments. + References No definition available. + Details
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- Definition The percentage of loans in the primary default inventory that have been delinquent for at least four payments but no more than eleven payments. + References No definition available. + Details
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- References No definition available. + Details
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- Definition The number of loans included in the pool insurance notice inventory as of the end of the reporting period. + 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 The number of loans in the primary default inventory that are in the claims received inventory. + References No definition available. + Details
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- Definition The percentage of loans in the primary default inventory that are in the claims received inventory. + References No definition available. + Details
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- Definition The number of loans that have been in the primary default inventory for at least four months but no greater than eleven months as of the balance sheet date. + References No definition available. + Details
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- Definition The percentage of loans that have been in the primary default inventory for at least four months but no greater than eleven months as of the balance sheet date. + References No definition available. + Details
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- Definition The percentage of loans in the primary default inventory. + References No definition available. + Details
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- Definition The number of loans that have been in the primary default inventory for three months or less as of the balance sheet date. + References No definition available. + Details
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- Definition The percentage of loans that have been in the primary default inventory for three months or less as of the balance sheet date. + References No definition available. + Details
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Data Type: | num:percentItemType
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- Definition The number of loans that have been in the primary default inventory for twelve months or more as of the balance sheet date. + References No definition available. + Details
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- Definition Primary Default Inventory Twelve Months Or More, Percent Of Primary Default Inventory In Default For Twelve Months Or More In Default For More Than Thirty Six Consecutive Months + References No definition available. + Details
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- Definition The percentage of loans that have been in the primary default inventory for twelve months or more as of the balance sheet date. + References No definition available. + Details
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- Definition Primary Delinquent Inventory Twelve Payments Or More, Percent Of Primary Delinquent Inventory Delinquent For Twelve Payments or More Delinquent For Thirty Six Payments or More + References No definition available. + Details
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