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Fair Value Option (Tables) | 9 Months Ended
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Sep. 30, 2012
Fair Value Option [Abstract] |
Gains And Losses Due To Changes In Fair Value Of Investments | The following table presents gains (losses) due to changes in fair value of investments that are measured at fair value pursuant to application of the fair value option:
| Three Months Ended September 30, |  | Nine Months Ended September 30,
| 2012 |  | 2011 |  | 2012 |  | 2011
| (Amounts in thousands)
Fixed maturity securities | $ | 19,198 |  |  | $ | 25,525 |  |  | $ | 50,013 |  |  | $ | 49,834 |
Equity securities | 25,629 |  |  | (87,009 | ) |  | 20,153 |  |  | (69,858 | )
Short-term investments | (44 | ) |  | (2,828 | ) |  | (828 | ) |  | (2,854 | )
Total | $ | 44,783 |  |  | $ | (64,312 | ) |  | $ | 69,338 |  |  | $ | (22,878 | )

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- Definition Tabular disclosure of unrealized gains and losses on investments. + References No definition available. + Details
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