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Fair Value Option (Tables) | 6 Months Ended
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Jun. 30, 2017
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 the application of the fair value option:
| Three Months Ended June 30, |  | Six Months Ended June 30,
| 2017 |  | 2016 |  | 2017 |  | 2016
| (Amounts in thousands)
Fixed maturity securities | $ | 25,622 |  |  | $ | 28,871 |  |  | $ | 35,909 |  |  | $ | 40,434 |
Equity securities | (5,080 | ) |  | 8,666 |  |  | 6,462 |  |  | 15,573 |
Short-term investments | (267 | ) |  | (410 | ) |  | (240 | ) |  | (349 | )
Total gains | $ | 20,275 |  |  | $ | 37,127 |  |  | $ | 42,131 |  |  | $ | 55,658 |

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- Definition Fair Value Option [Abstract] + References No definition available. + Details
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- Definition Tabular disclosure of unrealized gains and losses on investments. + References No definition available. + Details
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