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Loss Reserves - Reconciliation of Beginning and Ending Balances (Details) - USD ($) $ in Thousands | 9 Months Ended
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Sep. 30, 2019 | Sep. 30, 2018
Loss Reserve [Roll Forward] |  |
Reserve at beginning of period | $ 674,019 | $ 985,635
Less reinsurance recoverable | 33,328 | 48,474
Net reserve at beginning of period | 640,691 | 937,161
Losses and LAE incurred in respect of delinquency notices received in: |  |
Current year | 142,644 | 155,808
Prior years | (47,760) | (146,931)
Total losses incurred | 94,884 | 8,877
Losses and LAE paid in respect of delinquency notices received in: |  |
Current year | 980 | 2,449
Prior years | 165,844 | 257,808
Reinsurance terminations | (13,980) | (1,984)
Total losses paid | 152,844 | 258,273
Net reserve at end of period | 582,731 | 687,765
Plus reinsurance recoverables | 19,566 | 33,281
Reserve at end of period | $ 602,297 | $ 721,046

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