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Investments (Components Of Net Realized and Unrealized Gains and Losses (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2020 | Mar. 31, 2019
Gain (Loss) on Securities [Line Items] |  |
Net realized gains (losses) on disposals of securities, fixed income securities (excluding OTTI charges) | $ 4,100 | $ 3,444
OTTI Charges | 31,629 | 104
Net realized (losses) gains | (27,529) | 3,340
Unrealized Gains Losses on Equity Securities | (27,200) |
Net realized and unrealized investment (losses) gains | (44,666) | 13,451
Total unrealized (losses) gains recognized in income on equity securities | (17,137) | 10,111
Increase in net realized and unrealized investment losses | (58,100) |
Fixed Income Securities [Member] |  |
Gain (Loss) on Securities [Line Items] |  |
Net realized gains (losses) on disposals of securities, fixed income securities (excluding OTTI charges) | 4,276 | 1,143
Equity Securities [Member] |  |
Gain (Loss) on Securities [Line Items] |  |
Net realized gains (losses) on disposals of securities, fixed income securities (excluding OTTI charges) | (3) | 2,280
Short-Term Investments [Member] |  |
Gain (Loss) on Securities [Line Items] |  |
Net realized gains (losses) on disposals of securities, fixed income securities (excluding OTTI charges) | (168) | 14
Other Investments [Member] |  |
Gain (Loss) on Securities [Line Items] |  |
Net realized gains (losses) on disposals of securities, fixed income securities (excluding OTTI charges) | (5) | 7
OTTI Charges | $ 0 | $ 39

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