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Loss Reserves - Reconciliation of Changes in Loss Reserves (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Loss Reserve [Roll Forward] |  |  |  |
Reserve at beginning of year | $ 555,334 | $ 674,019 | $ 985,635 |
Less reinsurance recoverable | 95,042 | 21,641 | 33,328 | $ 48,474
Net reserve at beginning of year | 785,495 | 533,693 | 640,691 | $ 937,161
Losses incurred: [Abstract] |  |  |  |
Current year | 345,170 | 189,581 | 203,928 |
Prior years | 19,604 | (71,006) | (167,366) |
Total losses incurred | 364,774 | 118,575 | 36,562 |
Losses paid [Abstract] |  |  |  |
Current year | 3,069 | 4,018 | 7,298 |
Prior years | 109,923 | 235,551 | 327,743 |
Reinsurance terminations | (20) | (13,996) | (2,009) |
Total losses paid | 112,972 | 225,573 | 333,032 |
Reserve at end of year | $ 880,537 | $ 555,334 | $ 674,019 |

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- Definition The amount needed 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 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (cc) -URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 + Details
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- Definition Liability as of the balance sheet date for amounts representing estimated cost of settling unpaid claims under the terms of the underlying insurance policies, less estimated reinsurance recoveries on such claims. This includes an estimate for claims which have been incurred but not reported. Claim adjustment expenses represent the costs estimated to be incurred in the settlement of unpaid claims. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(13)(a)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (cc) -URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 + Details
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