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UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2018 | Dec. 31, 2017
Fixed income securities, available for sale, amortized cost | $ 5,273.4 | $ 5,201.2
Short-term investments, trading at fair value, amortized cost | 1,434.2 | 1,634.9
Equity securities, trading at fair value, cost | 0.0 | 414.8
Catastrophe bonds, trading at fair value, cost | 37.7 | 33.5
Cash and cash equivalents, within consolidated VIEs | $ 41.0 | $ 166.6
Ordinary shares, par value (in usd per share) | $ 0.0015144558 | $ 0.0015144558
Ordinary shares, issued (in shares) | 59,697,669 | 59,474,085
Preference shares, par value (in usd per share) | $ 0.0015144558 | $ 0.0015144558
5.95% preference shares |  |
Preference shares, issued (in shares) | 11,000,000 | 11,000,000
Preference shares, rate | 5.95% | 5.95%
Preference shares, par value (in usd per share) | $ 0.0015144558 | $ 0.0015144558
5.625% preference shares |  |
Preference shares, issued (in shares) | 10,000,000 | 10,000,000
Preference shares, rate | 5.625% | 5.625%
Preference shares, par value (in usd per share) | $ 0.0015144558 | $ 0.0015144558
Short-term Investments |  |
Short term investments, available for sale at fair value | $ 120.4 | $ 90.0
Short term investments, trading at fair value |  |
Short term investments, trading at fair value | $ 4.3 | $ 73.0

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