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Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Fixed income securities, amortized cost | $ 3,451,149 | $ 5,271,818
Other Investments | $ 391,217 | $ 431,630
Preferred stock, par value | $ 0.01 | $ 0.01
Preferred stock, shares authorized | 20,000,000 | 20,000,000
Preferred stock, shares issued | 0 | 0
Preferred Stock, Shares Outstanding | 0 | 0
Common stock, par value | $ 0.01 | $ 0.01
Common stock, shares authorized | 130,000,000 | 130,000,000
Common Stock, Shares, Outstanding | 45,336,278 |
Fixed Income Securities [Member] |  |
Fixed income securities, amortized cost | $ 3,020,744 | $ 4,614,623
Equity investments in pooled funds [Member] |  |
Other Investments | 351,049 | 366,939
Other Investment Not Readily Marketable, Fair Value | 351,049 | 396,689
Collateral Pledged [Member] | Fixed Income Securities [Member] |  |
Fixed income securities, amortized cost | 0 | 99,719
Parent Company [Member] |  |
Fixed income securities, amortized cost | 151,007 | 239,476
Other Investments | $ 40,168 | $ 64,691
Preferred stock, par value | $ 0.01 | $ 0.01
Preferred stock, shares authorized | 20,000,000 | 20,000,000
Common stock, par value | $ 0.01 | $ 0.01
Common stock, shares authorized | 130,000,000 | 130,000,000
Common stock, shares issued | 45,365,170 | 45,275,982
Common Stock, Shares, Outstanding | 45,365,170 | 45,275,982
Treasury stock, shares | 28,892 | 24,816
Short-term Investments [Member] |  |
Fixed income securities, amortized cost | $ 430,405 | $ 557,476
Short-term Investments [Member] | Parent Company [Member] |  |
Fixed income securities, amortized cost | $ 192,996 | $ 69,531

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