v2.4.0.6

Investments (Schedule of Net Investment Income) (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended
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Mar. 31, 2013 | Mar. 31, 2012
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |
Investment income before investment expenses | $ 46,555 | $ 69,672
Investment expenses | (2,940) | (2,701)
Net investment income (loss) | 43,615 | 66,971
Fixed maturity investments [Member] |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |
Investment income before investment expenses | 24,310 | 26,333
Short term investments [Member] |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |
Investment income before investment expenses | 318 | 500
Equity investments [Member] |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |
Investment income before investment expenses | 0 | 170
Other investments, Hedge funds and private equity investments [Member] |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |
Investment income before investment expenses | 14,880 | 28,473
Other investments, Other [Member] |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |
Investment income before investment expenses | 6,995 | 14,170
Cash and cash equivalents [Member] |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |
Investment income before investment expenses | $ 52 | $ 26

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- Definition This item represents the total of all interest and dividend income on fixed maturity investments, short term investments, equity investments trading and other investments (including any amortization/accretion of discounts/premiums), interest income earned on cash and cash equivalents and net gain or loss, both realized and unrealized, on other investments, before investment expenses. + References No definition available. + Details
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- Definition Total expenses related to the generation of investment income in debt and equity securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.9) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 + Details
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- Definition The income earned from investments in securities and property, equipment and other capital assets. It includes rent from property and equipment, dividends from shares in corporations, and interest from bonds, loans, mortgages, derivatives, commercial paper, bank accounts, certificates of deposits, treasuries, and other financial securities. It does not include realized gains and losses on investments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 16 -Article 12 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.2) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 2 -Article 7 + Details
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