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Financial Instruments (Details 1) - USD ($) $ in Millions | Jun. 30, 2016 | Dec. 31, 2015
--- | --- | ---
Marketable Debt and Equity Securities |  |
Fair Value | $ 5,912.4 | $ 4,880.9
Gross Unrealized Gains | 13.2 | 0.3
Gross Unrealized Losses | (2.1) | (10.6)
Amortized Cost | 5,901.3 | 4,891.2
Corporate debt securities Current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 913.4 | 394.3
Gross Unrealized Gains | 0.3 | 0.0
Gross Unrealized Losses | (0.2) | (0.5)
Amortized Cost | 913.3 | 394.8
Corporate debt securities Non-current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 1,376.9 | 1,116.6
Gross Unrealized Gains | 7.8 | 0.1
Gross Unrealized Losses | (0.4) | (4.1)
Amortized Cost | 1,369.5 | 1,120.6
Government securities Current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 1,521.3 | 1,723.4
Gross Unrealized Gains | 0.6 | 0.1
Gross Unrealized Losses | 0.0 | (1.1)
Amortized Cost | 1,520.7 | 1,724.4
Government securities Non-current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 1,452.1 | 1,152.5
Gross Unrealized Gains | 3.1 | 0.0
Gross Unrealized Losses | (0.6) | (3.1)
Amortized Cost | 1,449.6 | 1,155.6
Mortgage and other asset backed securities Current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 0.1 | 2.8
Gross Unrealized Gains | 0.0 | 0.0
Gross Unrealized Losses | 0.0 | 0.0
Amortized Cost | 0.1 | 2.8
Mortgage and other asset backed securities Non-current |  |
Marketable Debt and Equity Securities |  |
Fair Value | 648.6 | 491.3
Gross Unrealized Gains | 1.4 | 0.1
Gross Unrealized Losses | (0.9) | (1.8)
Amortized Cost | 648.1 | 493.0
Marketable equity securities |  |
Marketable Debt and Equity Securities |  |
Fair Value | 32.4 | 37.5
Gross Unrealized Gains | 0.9 | 9.2
Gross Unrealized Losses | (2.1) | 0.0
Amortized Cost | $ 33.6 | $ 28.3

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