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Investments (Tables) | 12 Months Ended
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Dec. 31, 2019
Investments [Abstract] |
Gains And Losses Due To Changes In Fair Value | 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:
| Year Ended December 31,
| 2019 |  | 2018 |  | 2017
| (Amounts in thousands)
Fixed maturity securities | $ | 104,379 |  |  | $ | (53,927 | ) |  | $ | 50,403 |
Equity securities | 90,920 |  |  | (77,494 | ) |  | 37,486 |
Short-term investments | 1,295 |  |  | (1,237 | ) |  | 38 |
Total gains (losses) | $ | 196,594 |  |  | $ | (132,658 | ) |  | $ | 87,927 |
Gross Gains And Losses Realized On Sales Of Investments | The following table presents gross gains (losses) realized on the sales of investments:
| Year Ended December 31,
| 2019 |  | 2018 |  | 2017
| (Amounts in thousands)
| Gross Realized Gains |  | Gross Realized Losses |  | Net |  | Gross Realized Gains |  | Gross Realized Losses |  | Net |  | Gross Realized Gains |  | Gross Realized Losses |  | Net
Fixed maturity securities | $ | 2,413 |  |  | $ | (1,066 | ) |  | $ | 1,347 |  |  | $ | 549 |  |  | $ | (3,563 | ) |  | $ | (3,014 | ) |  | $ | 604 |  |  | $ | (2,701 | ) |  | $ | (2,097 | )
Equity securities | 47,411 |  |  | (28,089 | ) |  | 19,322 |  |  | 43,420 |  |  | (45,607 | ) |  | (2,187 | ) |  | 20,835 |  |  | (23,048 | ) |  | (2,213 | )
Short-term investments | 177 |  |  | (2,133 | ) |  | (1,956 | ) |  | 61 |  |  | (2,429 | ) |  | (2,368 | ) |  | 21 |  |  | (20 | ) |  | 1 |
Estimated Fair Values Of Investments | The following table presents the estimated fair values of the Company's fixed maturity securities at December 31, 2019 by contractual maturity. Expected maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties.
| Estimated Fair Value
| (Amounts in thousands)
Fixed maturity securities: |
Due in one year or less | $ | 105,929 |
Due after one year through five years | 548,638 |
Due after five years through ten years | 287,005 |
Due after ten years | 2,151,703 |
Total | $ | 3,093,275 |
Investment Income | The following table presents a summary of net investment income:
| Year Ended December 31,
| 2019 |  | 2018 |  | 2017
| (Amounts in thousands)
Fixed maturity securities | $ | 102,254 |  |  | $ | 102,198 |  |  | $ | 102,790 |
Equity securities | 32,233 |  |  | 30,496 |  |  | 18,554 |
Short-term investments | 12,381 |  |  | 8,789 |  |  | 8,753 |
Total investment income | $ | 146,868 |  |  | $ | 141,483 |  |  | $ | 130,097 |
Less: investment expense | (5,605 | ) |  | (5,645 | ) |  | (5,167 | )
Net investment income | $ | 141,263 |  |  | $ | 135,838 |  |  | $ | 124,930 |

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