v2.4.0.6

Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2012 | Dec. 31, 2011
--- | --- | ---
Total fixed maturity investments | $ 4,302,119 |  | $ 4,433,517 |
Short-term investments | 1,172,839 |  | 905,477 |
Equity investments trading | 53,080 |  | 50,560 |
Other investments | 806,782 |  | 748,984 |
Total other assets and (liabilities) | 53,504 |  | 16,071 |
Total assets and liabilities measured on recurring basis | 6,388,324 |  | 6,154,609 |
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Total fixed maturity investments | 1,309,243 |  | 885,152 |
Short-term investments | 0 |  | 0 |
Equity investments trading | 53,080 |  | 50,560 |
Other investments | 0 |  | 0 |
Total other assets and (liabilities) | (1,068) |  | (6,162) |
Total assets and liabilities measured on recurring basis | 1,361,255 |  | 929,550 |
Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Total fixed maturity investments | 2,965,038 |  | 3,520,604 |
Short-term investments | 1,172,839 |  | 905,477 |
Equity investments trading | 0 |  | 0 |
Other investments | 388,245 |  | 352,458 |
Total other assets and (liabilities) | 6,427 |  | (6,293) |
Total assets and liabilities measured on recurring basis | 4,532,549 |  | 4,772,246 |
Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Total fixed maturity investments | 27,838 |  | 27,761 |
Short-term investments | 0 |  | 0 |
Equity investments trading | 0 |  | 0 |
Other investments | 418,537 |  | 396,526 |
Total other assets and (liabilities) | 48,145 |  | 28,526 |
Total assets and liabilities measured on recurring basis | 494,520 |  | 452,813 |
U.S. treasuries [Member] |  |  |  |
Total fixed maturity investments | 1,309,243 |  | 885,152 |
U.S. treasuries [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Total fixed maturity investments | 1,309,243 |  | 885,152 |
U.S. treasuries [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
U.S. treasuries [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Agencies [Member] |  |  |  |
Total fixed maturity investments | 343,575 |  | 158,561 |
Agencies [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Agencies [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Total fixed maturity investments | 343,575 |  | 158,561 |
Agencies [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Non-U.S. government (Sovereign Debt) [Member] |  |  |  |
Total fixed maturity investments | 130,899 |  | 227,912 |
Non-U.S. government (Sovereign Debt) [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Non-U.S. government (Sovereign Debt) [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Total fixed maturity investments | 130,899 |  | 227,912 |
Non-U.S. government (Sovereign Debt) [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
FDIC guaranteed corporate [Member] |  |  |  |
Total fixed maturity investments | 103,554 |  | 423,630 |
FDIC guaranteed corporate [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
FDIC guaranteed corporate [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Total fixed maturity investments | 103,554 |  | 423,630 |
FDIC guaranteed corporate [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Non-U.S. government-backed corporate [Member] |  |  |  |
Total fixed maturity investments | 501,160 |  | 641,082 |
Non-U.S. government-backed corporate [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Non-U.S. government-backed corporate [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Total fixed maturity investments | 501,160 |  | 641,082 |
Non-U.S. government-backed corporate [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Corporate [Member] |  |  |  |
Total fixed maturity investments | 1,146,211 |  | 1,206,904 |
Corporate [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Corporate [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Total fixed maturity investments | 1,118,373 |  | 1,179,143 |
Corporate [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Total fixed maturity investments | 27,838 |  | 27,761 |
Agency mortgage-backed [Member] |  |  |  |
Total fixed maturity investments | 319,215 |  | 441,749 |
Agency mortgage-backed [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Agency mortgage-backed [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Total fixed maturity investments | 319,215 |  | 441,749 |
Agency mortgage-backed [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Non-agency mortgage-backed [Member] |  |  |  |
Total fixed maturity investments | 108,047 |  | 104,771 |
Non-agency mortgage-backed [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Non-agency mortgage-backed [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Total fixed maturity investments | 108,047 |  | 104,771 |
Non-agency mortgage-backed [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Commercial mortgage-backed [Member] |  |  |  |
Total fixed maturity investments | 329,343 |  | 325,729 |
Commercial mortgage-backed [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Commercial mortgage-backed [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Total fixed maturity investments | 329,343 |  | 325,729 |
Commercial mortgage-backed [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Asset-backed [Member] |  |  |  |
Total fixed maturity investments | 10,872 |  | 18,027 |
Asset-backed [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Asset-backed [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Total fixed maturity investments | 10,872 |  | 18,027 |
Asset-backed [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Total fixed maturity investments | 0 |  | 0 |
Private equity partnerships [Member] |  |  |  |
Other investments | 389,451 |  | 367,909 |
Private equity partnerships [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Other investments | 0 |  | 0 |
Private equity partnerships [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Other investments | 0 |  | 0 |
Private equity partnerships [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Other investments | 389,451 |  | 367,909 |
Senior secured bank loan funds [Member] |  |  |  |
Other investments | 266,141 |  | 257,870 |
Senior secured bank loan funds [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Other investments | 0 |  | 0 |
Senior secured bank loan funds [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Other investments | 245,141 |  | 237,815 |
Senior secured bank loan funds [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Other investments | 21,000 |  | 20,055 |
Catastrophe bonds [Member] |  |  |  |
Other investments | 95,827 |  | 70,999 |
Catastrophe bonds [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Other investments | 0 |  | 0 |
Catastrophe bonds [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Other investments | 95,827 |  | 70,999 |
Catastrophe bonds [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Other investments | 0 |  | 0 |
Non-U.S. fixed income funds [Member] |  |  |  |
Other investments | 31,713 |  | 28,862 |
Non-U.S. fixed income funds [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Other investments | 0 |  | 0 |
Non-U.S. fixed income funds [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Other investments | 31,713 |  | 28,862 |
Non-U.S. fixed income funds [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Other investments | 0 |  | 0 |
Hedge Funds [Member] |  |  |  |
Other investments | 22,310 |  | 21,344 |
Hedge Funds [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Other investments | 0 |  | 0 |
Hedge Funds [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Other investments | 15,564 |  | 14,782 |
Hedge Funds [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Other investments | 6,746 |  | 6,562 |
Miscellaneous other investments [Member] |  |  |  |
Other investments | 1,340 |  | 2,000 |
Miscellaneous other investments [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Other investments | 0 |  | 0 |
Miscellaneous other investments [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Other investments | 0 |  | 0 |
Miscellaneous other investments [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Other investments | 1,340 |  | 2,000 |
Assumed and ceded reinsurance contracts [Member] |  |  |  |
Total other assets and (liabilities) | 6,163 |  | 2,115 |
Assumed and ceded reinsurance contracts [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Total other assets and (liabilities) | 0 |  | 0 |
Assumed and ceded reinsurance contracts [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Total other assets and (liabilities) | 0 |  | 0 |
Assumed and ceded reinsurance contracts [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Total other assets and (liabilities) | 6,163 |  | 2,115 |
Derivatives [Member] |  |  |  |
Total other assets and (liabilities) | 33,405 | [1] | 3,312 | [1]
Derivatives [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Total other assets and (liabilities) | 413 |  | 707 | [1]
Derivatives [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Total other assets and (liabilities) | 6,427 |  | (6,293) | [1]
Derivatives [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Total other assets and (liabilities) | 26,565 |  | 8,898 | [1]
Other [Member] |  |  |  |
Total other assets and (liabilities) | 13,936 |  | 10,644 |
Other [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |
Total other assets and (liabilities) | (1,481) |  | (6,869) |
Other [Member] | Significant Other Observable Inputs (Level 2) [Member] |  |  |  |
Total other assets and (liabilities) | 0 |  | 0 |
Other [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |  |
Total other assets and (liabilities) | $ 15,417 |  | $ 17,513 |
[1] | See "Note 11. Derivative Instruments" for additional information related to the fair value by type of contract, of derivatives entered into by the Company.

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