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Loss Reserves - Narrative (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 USD ($) Payment loan | Dec. 31, 2021 USD ($) loan | Dec. 31, 2020 USD ($) loan
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 | Payment | 2 |  |
Change in loss reserves (+/-) | $ (325,534) | $ 2,985 | $ 325,203
Total prior year loss development | (404,130) | (60,015) | $ 19,604
Premium refund liability, expected claim payments | $ 25,500 | $ 37,300 |
Other items removed from inventory | loan | 289 | 695 | 0
Prior years | $ 49,626 | $ 68,769 | $ 109,923
Current year | $ 149,565 | $ 124,592 | $ 345,170
Pool insurance notice inventory (in number of loans) | loan | 391 | 498 | 680
Settlements for commutations of coverage, pools of nonperforming loans |  |  |
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |
Prior years | $ 4,600 | $ 13,800 |
$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 (+/-) | 10,000 |  |
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 (+/-) | 15,000 |  |
Change in estimates related to IBNR reserves |  |  |
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |
Current year | $ 2,300 | (5,900) |
Probable Loss On Litigation Claims Paying Practices |  |  |
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items] |  |  |
Total prior year loss development |  | $ 6,300 |

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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 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 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 https://asc.fasb.org/extlink&oid=126954810&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 https://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 + Details
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- Definition Amount, after effects of reinsurance, of expense for claims incurred in the current reporting period and related claims settlement costs. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 + 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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 + Details
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