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Losses And Loss Adjustment Expenses (Activity In The Reserves For Losses And Loss Adjustment Expenses) (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Insurance Loss Reserves [Abstract] |  |  |
Gross reserves at January 1 | $ 985,279 | $ 1,034,205 | $ 1,053,334
Less reinsurance recoverable | (7,921) | (6,805) | (7,748)
Net reserves at January 1 | 977,358 | 1,027,400 | 1,045,586
Incurred losses and loss adjustment expense related to: |  |  |
Current year | 1,919,116 | 1,810,711 | 1,838,824
Prior years | 42,332 | 18,494 | (13,058)
Total incurred losses and loss adjustment expenses | 1,961,448 | 1,829,205 | 1,825,766
Loss and loss adjustment expense payments related to: |  |  |
Current year | 1,314,748 | 1,265,188 | 1,240,696
Prior years | 600,090 | 614,059 | 603,256
Total payments | 1,914,838 | 1,879,247 | 1,843,952
Net reserves at year-end | 1,023,968 | 977,358 | 1,027,400
Reinsurance recoverable | 12,155 | 7,921 | 6,805
Gross reserves at year-end | $ 1,036,123 | $ 985,279 | $ 1,034,205

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- Definition Total amount of payments made during the reporting period to settle insured claims and pay costs incurred in the claims settlement process. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 94-5 -Paragraph 11 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Financial Reporting Release (FRR) -Number 403 -Paragraph 04 -Subparagraph b Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6482485&loc=d3e14764-158437 + Details
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