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Financial Instruments (Details 1) - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Marketable Debt and Equity Securities |  |
Fair Value | $ 4,781.4 | $ 5,398.0
Gross Unrealized Gains | 4.3 | 2.9
Gross Unrealized Losses | (8.9) | (11.2)
Amortized Cost | 4,786.0 | 5,406.3
Corporate debt securities Current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 1,288.5 | 1,408.6
Gross Unrealized Gains | 0.1 | 0.2
Gross Unrealized Losses | (0.8) | (0.6)
Amortized Cost | 1,289.2 | 1,409.0
Corporate debt securities Non-current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 1,212.2 | 1,255.2
Gross Unrealized Gains | 2.1 | 1.2
Gross Unrealized Losses | (3.3) | (4.7)
Amortized Cost | 1,213.4 | 1,258.7
Government securities Current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 664.4 | 1,156.0
Gross Unrealized Gains | 0.2 | 0.2
Gross Unrealized Losses | (0.4) | (0.3)
Amortized Cost | 664.6 | 1,156.1
Government securities Non-current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 1,073.8 | 1,016.5
Gross Unrealized Gains | 0.8 | 0.5
Gross Unrealized Losses | (3.0) | (3.4)
Amortized Cost | 1,076.0 | 1,019.4
Mortgage and other asset backed securities Current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 3.3 | 4.0
Gross Unrealized Gains | 0.0 | 0.0
Gross Unrealized Losses | 0.0 | 0.0
Amortized Cost | 3.3 | 4.0
Mortgage and other asset backed securities Non-current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 539.2 | 557.7
Gross Unrealized Gains | 1.1 | 0.8
Gross Unrealized Losses | (1.4) | (2.2)
Amortized Cost | 539.5 | 559.1
Marketable equity securities |  |
Marketable Debt and Equity Securities |  |
Fair Value | 18.7 | 24.9
Gross Unrealized Gains | 0.0 | 0.7
Gross Unrealized Losses | (14.9) | (9.3)
Amortized Cost | $ 33.6 | $ 33.5

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