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Loss Reserves - Narrative (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 USD ($) loan Payment | Dec. 31, 2019 USD ($) loan | Dec. 31, 2018 USD ($) loan
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |
Loss reserves | $ 325,203 | $ (118,685) | $ (311,616)
Minimum number of payments past due to be in default | Payment | 2 |  |
Premium refund liability, expected claim payments | $ 30,000 | $ 30,000 |
Percentage of prior year default inventory resolved (in hundredths) |  | 69.00% | 73.00%
Other items removed from inventory | loan | 0 | 639 | 1,578
Losses for unpaid claims and adjustment expense | $ 109,923 | $ 235,551 | $ 327,743
Pool insurance notice inventory (in number of loans) | loan | 680 | 653 | 859
Settlements for commutations of coverage, pools of nonperforming loans |  |  |
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |
Losses for unpaid claims and adjustment expense |  | $ 30,000 | $ 50,000
Settlements for claims paying practices |  |  |
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |
Losses for unpaid claims and adjustment expense |  | $ 23,500 |
$1,000 Increase/Decrease In Average Severity Reserve Factor |  |  |
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |
Loss reserves | $ 16,000 |  |
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] |  |  |
Loss reserves | $ 34,000 |  |

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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 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 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 carrying amount for the estimate of premiums to be refunded on expected claim payments. + References No definition available. + Details
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- Definition Other deductions from the primary default inventory, including items removed for settlements + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + 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 -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 + Details
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- Definition Amount, after effects of reinsurance, of payments to settle claims incurred in prior periods and related claims settlement costs. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 + Details
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