v2.4.0.6

SEGMENT INFORMATION (DETAILS 3) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2011 | Sep. 30, 2011 | Jun. 30, 2011 | Mar. 31, 2011 | Dec. 31, 2010 | Sep. 30, 2010 | Jun. 30, 2010 | Mar. 31, 2010 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned | $ 846,753 | $ 839,992 | $ 840,014 | $ 788,201 | $ 757,318 | $ 758,873 | $ 735,027 | $ 696,192 | $ 3,314,961 | $ 2,947,410 | $ 2,791,764
Insurance [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 1,429,687 | 1,206,493 | 1,157,966
Insurance [Member] | Property [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 385,291 | 337,525 | 268,469
Insurance [Member] | Marine [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 152,123 | 145,356 | 139,196
Insurance [Member] | Terrorism [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 35,213 | 32,486 | 34,001
Insurance [Member] | Aviation [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 70,681 | 66,636 | 64,245
Insurance [Member] | Credit And Political Risk [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 97,680 | 89,773 | 188,311
Insurance [Member] | Professional Lines [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 536,238 | 444,663 | 381,364
Insurance [Member] | Liability [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 89,555 | 87,481 | 82,380
Insurance [Member] | Accident And Health [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 62,906 | 2,573 | 0
Reinsurance [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 1,885,274 | 1,740,917 | 1,633,798
Reinsurance [Member] | Property [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 356,022 | 323,201 | 311,272
Reinsurance [Member] | Professional Lines [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 281,025 | 285,224 | 266,792
Reinsurance [Member] | Liability [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 230,872 | 232,014 | 227,511
Reinsurance [Member] | Other [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 28,028 | 29,082 | 31,851
Reinsurance [Member] | Catastrophe [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 456,858 | 454,954 | 451,085
Reinsurance [Member] | Credit And Bond [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 263,912 | 217,809 | 179,362
Reinsurance [Member] | Motor [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | 202,830 | 127,404 | 99,497
Reinsurance [Member] | Engineering [Member] |  |  |  |  |  |  |  |  |  |  |
Revenue by Product [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net premiums earned |  |  |  |  |  |  |  |  | $ 65,727 | $ 71,229 | $ 66,428

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- Definition Premiums earned on the income statement for all insurance and reinsurance contracts after subtracting any amounts ceded to another insurer and adding premiums assumed from other insurers. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(c)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 1 -Article 7 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 113 -Paragraph 27 -Subparagraph a, b -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 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.1) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 + Details
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