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Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands | Jun. 30, 2020 | Dec. 31, 2019
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Statement of Financial Position [Abstract] |  |
Amortized cost on fixed maturities trading investments | $ 3,207,125 | $ 2,973,276
Cost - equity security trading investments | 737,127 | 648,282
Cost - short-term investments | 335,556 | 494,060
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment | $ 294,479 | $ 312,060
Common Stock |  |
Common stock, shares authorized (in shares) | 70,000,000 |
Common stock, shares issued (in shares) | 55,358,000 |
Common stock, shares outstanding (in shares) | 55,358,000 |

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