v2.4.0.8

Fair Value Measurements - Fair Value Hierarchy (Details) (USD $) In Thousands, unless otherwise specified |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6 Months Ended |  |  |  |  |  |  |  |  |  |  |  |  |  |
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Jun. 30, 2013 | Dec. 31, 2012 | Jun. 30, 2013 Other investments [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] U.S. treasury bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] U.S. treasury bonds [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] U.S. agency bonds – mortgage-backed [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] U.S. agency bonds – mortgage-backed [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] U.S. agency bonds – other [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] U.S. agency bonds – other [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Non-U.S. government bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Non-U.S. government bonds [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Other mortgage-backed securities [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Other mortgage-backed securities [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Corporate bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Corporate bonds [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Municipal bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Municipal bonds [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] U.S. treasury bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] U.S. treasury bonds [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] U.S. agency bonds – mortgage-backed [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] U.S. agency bonds – mortgage-backed [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] U.S. agency bonds – other [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] U.S. agency bonds – other [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Non-U.S. government bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Non-U.S. government bonds [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Other mortgage-backed securities [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Other mortgage-backed securities [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Corporate bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Corporate bonds [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Municipal bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Other Observable Inputs (Level 2) [Member] Municipal bonds [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] U.S. treasury bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] U.S. treasury bonds [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] U.S. agency bonds – mortgage-backed [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] U.S. agency bonds – mortgage-backed [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] U.S. agency bonds – other [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] U.S. agency bonds – other [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Non-U.S. government bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Non-U.S. government bonds [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Other mortgage-backed securities [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Other mortgage-backed securities [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Corporate bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Corporate bonds [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Municipal bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Significant Unobservable Inputs (Level 3) [Member] Municipal bonds [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] Fixed Maturities [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] U.S. treasury bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] U.S. treasury bonds [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] U.S. agency bonds – mortgage-backed [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] U.S. agency bonds – mortgage-backed [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] U.S. agency bonds – other [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] U.S. agency bonds – other [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] Non-U.S. government bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] Non-U.S. government bonds [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] Other mortgage-backed securities [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] Other mortgage-backed securities [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] Corporate bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] Corporate bonds [Member] | Jun. 30, 2013 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] Municipal bonds [Member] | Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Total Fair Value [Member] Municipal bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fixed maturities, fair value |  |  |  |  |  | $ 17,446 | $ 43,931 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 |  |  | $ 0 | $ 0 | $ 1,218,486 | $ 992,174 | $ 12,856 | $ 13,089 | $ 58,481 | $ 57,433 | $ 27,463 | $ 24,068 | $ 1,366,640 | $ 1,354,154 | $ 13,495 | $ 133,848 |  |  | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 |  |  |  | $ 17,446 | $ 43,931 | $ 1,218,486 | $ 992,174 | $ 12,856 | $ 13,089 | $ 58,481 | $ 57,433 | $ 27,463 | $ 24,068 | $ 1,366,640 | $ 1,354,154 | $ 13,495 | $ 133,848
Other investments, fair value |  |  |  | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4,438 | 2,901 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4,438 | 2,901 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total |  |  |  | 17,446 | 43,931 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,697,421 | 2,574,766 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4,438 | 2,901 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,719,305 | 2,621,598 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of total assets |  |  |  | 0.40% | 1.10% |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 61.20% | 62.20% |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.10% | 0.10% |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 61.70% | 63.40% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percent of fixed maturities valued by a pricing service |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 99.80% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other investments | $ 4,438 | $ 2,901 | $ 4,438 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other investments, percent of assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.20% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
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- Definition Other investments not otherwise specified in the taxonomy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 12 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph g -Article 7 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(f,g)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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