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Investments (Components Of Net Realized and Unrealized Gains, Excluding OTTI Charges) (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017
Schedule of Realized and Unrealized Gains and Losses [Line Items] |  |  |
Unrealized holding losses on equity securities | $ (5,100) |  |
Net realized (losses) gains on disposals of securities, fixed income securities | (3,335) |  | $ 1,964
Total net realized gains (excluding OTTI charges) | 4,731 |  | 2,430
Other than Temporary Impairment Losses, Investments | (1,212) |  | (3,475)
Net realized investment gains (losses) | 3,519 |  | (1,045)
Unrealized losses on equity securities | (14,068) | [1] | 0
Total net realized and unrealized losses | (10,549) |  | (1,045)
HTM fixed income securities realized gain | 2 |  | 0
HTM fixed income securities realized losses | 0 |  | (1)
Equity securities realized gains | 8,399 |  |
Equity securities realized losses | (330) |  |
Short term investments realized gains | 1 |  | 0
Short term investments realized losses | (4) |  | 0
Other investments realized gains | 0 |  | 480
Other investments realized losses | 0 |  | (14)
Proceeds from sale of available for sale fixed income securities | 675,400 |  | 594,800
Proceeds from sale of equity securities | 40,740 |  |
Proceeds from sale of equity securities, available-for-sale |  |  | 5,503
Fixed Income Securities [Member] |  |  |
Schedule of Realized and Unrealized Gains and Losses [Line Items] |  |  |
AFS securities realized gains | 2,623 |  | 3,552
AFS securities realized losses | (5,960) |  | (1,587)
Equity Securities [Member] |  |  |
Schedule of Realized and Unrealized Gains and Losses [Line Items] |  |  |
Total net realized gains (excluding OTTI charges) | 8,069 |  | 0
AFS securities realized gains |  |  | 0
AFS securities realized losses |  |  | 0
Short-Term Investments [Member] |  |  |
Schedule of Realized and Unrealized Gains and Losses [Line Items] |  |  |
Total net realized gains (excluding OTTI charges) | (3) |  | 0
Other Investments [Member] |  |  |
Schedule of Realized and Unrealized Gains and Losses [Line Items] |  |  |
Total net realized gains (excluding OTTI charges) | $ 0 |  | $ (466)
[1] | Unrealized holding losses in First Quarter 2018 on equity securities held as of March 31, 2018 was $5.1 million.

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