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Loss And Loss Adjustment Expense Reserves (Activity In The Reserves For Losses And Loss Adjustment Expenses) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] |  |  |
Gross reserves at January 1 | $ 2,226,430 | $ 1,991,304 | $ 1,921,255
Reissuance recoverables on unpaid losses, beginning of period | 41,379 | 54,461 | 76,100
Net reserves at January 1 | 2,185,051 | 1,936,843 | 1,845,304
Incurred losses and loss adjustment expenses related to: |  |  |
Current year | 3,314,938 | 2,786,246 | 2,372,364
Prior years | 47,281 | (26,091) | 22,979
Total incurred losses and loss adjustment expenses | 3,362,219 | 2,760,155 | 2,395,343
Loss and loss adjustment expense payments related to: |  |  |
Current year | 1,862,006 | 1,601,998 | 1,366,661
Prior years | 1,125,677 | 909,949 | 937,143
Total payments | 2,987,683 | 2,511,947 | 2,303,804
Net reserves at December 31 | 2,559,587 | 2,185,051 | 1,936,843
Reissuance recoverables on unpaid losses, end of period | 25,323 | 41,379 | 54,461
Gross reserves at December 31 | 2,584,910 | 2,226,430 | 1,991,304
Cumulative Effect, Period of Adoption, Adjustment |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] |  |  |
Reissuance recoverables on unpaid losses, beginning of period | 0 | 0 | (149)
Loss and loss adjustment expense payments related to: |  |  |
Reissuance recoverables on unpaid losses, end of period |  | 0 | 0
Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] |  |  |
Reissuance recoverables on unpaid losses, beginning of period | $ 41,379 | 54,461 | 75,951
Net reserves at January 1 |  | 1,936,843 |
Loss and loss adjustment expense payments related to: |  |  |
Net reserves at December 31 |  |  | 1,936,843
Reissuance recoverables on unpaid losses, end of period |  | $ 41,379 | $ 54,461

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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 https://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 https://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 + Details
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- Definition Amount, after effects of reinsurance, of payments to settle claims incurred in the current period 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 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 https://asc.fasb.org/extlink&oid=126734703&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 https://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 https://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 + Details
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