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Financial Instruments (Details 1) - USD ($) $ in Millions | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Marketable Debt and Equity Securities |  |
Fair Value | $ 5,398.0 | $ 4,880.9
Gross Unrealized Gains | 2.9 | 0.3
Gross Unrealized Losses | (11.2) | (10.6)
Amortized Cost | 5,406.3 | 4,891.2
Corporate debt securities Current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 1,408.6 | 394.3
Gross Unrealized Gains | 0.2 | 0.0
Gross Unrealized Losses | (0.6) | (0.5)
Amortized Cost | 1,409.0 | 394.8
Corporate debt securities Non-current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 1,255.2 | 1,116.6
Gross Unrealized Gains | 1.2 | 0.1
Gross Unrealized Losses | (4.7) | (4.1)
Amortized Cost | 1,258.7 | 1,120.6
Government securities Current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 1,156.0 | 1,723.4
Gross Unrealized Gains | 0.2 | 0.1
Gross Unrealized Losses | (0.3) | (1.1)
Amortized Cost | 1,156.1 | 1,724.4
Government securities Non-current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 1,016.5 | 1,152.5
Gross Unrealized Gains | 0.5 | 0.0
Gross Unrealized Losses | (3.4) | (3.1)
Amortized Cost | 1,019.4 | 1,155.6
Mortgage and other asset backed securities Current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 4.0 | 2.8
Gross Unrealized Gains | 0.0 | 0.0
Gross Unrealized Losses | 0.0 | 0.0
Amortized Cost | 4.0 | 2.8
Mortgage and other asset backed securities Non-current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 557.7 | 491.3
Gross Unrealized Gains | 0.8 | 0.1
Gross Unrealized Losses | (2.2) | (1.8)
Amortized Cost | 559.1 | 493.0
Marketable equity securities |  |
Marketable Debt and Equity Securities |  |
Fair Value | 24.9 | 37.5
Gross Unrealized Gains | 0.7 | 9.2
Gross Unrealized Losses | (9.3) | 0.0
Amortized Cost | $ 33.5 | $ 28.3

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