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Financial Instruments (Details 1) - USD ($) $ in Millions | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | ---
Marketable Debt and Equity Securities |  |
Fair Value | $ 4,880.9 | $ 2,111.1
Gross Unrealized Gains | 0.3 | 0.7
Gross Unrealized Losses | (10.6) | (2.4)
Amortized Cost | 4,891.2 | 2,112.8
Corporate debt securities Current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 394.3 | 370.4
Gross Unrealized Gains | 0.0 | 0.0
Gross Unrealized Losses | (0.5) | (0.2)
Amortized Cost | 394.8 | 370.6
Corporate debt securities Non-current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 1,116.6 | 692.6
Gross Unrealized Gains | 0.1 | 0.2
Gross Unrealized Losses | (4.1) | (1.5)
Amortized Cost | 1,120.6 | 693.9
Government securities Current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 1,723.4 | 269.9
Gross Unrealized Gains | 0.1 | 0.0
Gross Unrealized Losses | (1.1) | (0.1)
Amortized Cost | 1,724.4 | 270.0
Government securities Non-current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 1,152.5 | 579.9
Gross Unrealized Gains | 0.0 | 0.3
Gross Unrealized Losses | (3.1) | (0.4)
Amortized Cost | 1,155.6 | 580.0
Mortgage and other asset backed securities Current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 2.8 | 0.2
Gross Unrealized Gains | 0.0 | 0.0
Gross Unrealized Losses | 0.0 | 0.0
Amortized Cost | 2.8 | 0.2
Mortgage and other asset backed securities Non-current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 491.3 | 198.1
Gross Unrealized Gains | 0.1 | 0.2
Gross Unrealized Losses | (1.8) | (0.2)
Amortized Cost | 493.0 | 198.1
Marketable equity securities |  |
Marketable Debt and Equity Securities |  |
Fair Value | 37.5 | 6.9
Gross Unrealized Gains | 9.2 | 1.2
Gross Unrealized Losses | 0.0 | (0.2)
Amortized Cost | $ 28.3 | $ 5.9

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