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Investments (Schedule of Components of Net Realized and Unrealized Gains and Losses Excluding OTTI (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Gain (Loss) on Securities [Line Items] |  |  |  |
Net realized gains (losses) on disposals of securities (excluding OTTI) | $ 573 | $ 20,425 | $ 7,288 | $ 26,752
OTTI benefit (expense) | 2,810 | (2,291) | (24,486) | (3,366)
Net realized gains (losses) | 3,383 | 18,134 | (17,198) | 23,386
Total unrealized gains (losses) recognized in income on equity securities | 4,338 | (20,317) | (7,098) | (8,091)
Total net realized and unrealized investment gains (losses) | 7,721 | (2,183) | (24,296) | 15,295
Increase in net realized and unrealized investment gains | 9,900 |  |  |
Unrealized (Gain) Loss on Equity Securities Sold | 0 | (21,426) | 3 | (9,896)
Fixed Income Securities [Member] |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Net realized gains (losses) on disposals of securities (excluding OTTI) | 561 | (1,141) | 7,137 | 2,063
Commercial Mortgage Loans [Member] |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Net realized gains (losses) on disposals of securities (excluding OTTI) | 1 | 0 | 2 | 0
Equity Securities [Member] |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Net realized gains (losses) on disposals of securities (excluding OTTI) | 0 | 21,602 | (3) | 24,733
Unrealized (Gain) Loss on Equity Securities Sold |  | 21,400 |  |
Short-Term Investments [Member] |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Net realized gains (losses) on disposals of securities (excluding OTTI) | 11 | (36) | 157 | (21)
Other Investments [Member] |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Net realized gains (losses) on disposals of securities (excluding OTTI) | $ 0 | $ 0 | $ (5) | $ (23)

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- Definition The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting. + References No definition available. + Details
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- Definition The unrealized gains (losses) on equity securities sold during the period. + References No definition available. + Details
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