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Financial Instruments (Details 1) - USD ($) $ in Millions | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | $ 2,140.9 | $ 2,049.1
Gross unrealized gains | 1.6 | 2.3
Gross unrealized losses | (0.6) | (0.4)
Fair value | 2,141.9 | 2,051.0
Marketable equity securities, fair value | 2,141.9 | 2,051.0
Equity Securities, FV-NI, Cost |  | 1,239.5
Equity Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |  | 749.7
Equity Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, Before Tax |  | (14.9)
Equity Securities, FV-NI |  | 1,974.3
Corporate debt securities Current |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 979.7 | 897.8
Gross unrealized gains | 0.2 | 0.4
Gross unrealized losses | (0.4) | (0.2)
Fair value | 979.5 | 898.0
Corporate debt securities Non-current |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 356.0 | 402.5
Gross unrealized gains | 0.8 | 1.1
Gross unrealized losses | (0.1) | (0.1)
Fair value | 356.7 | 403.5
Government securities Current |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 340.5 | 380.6
Gross unrealized gains | 0.0 | 0.1
Gross unrealized losses | 0.0 | 0.0
Fair value | 340.5 | 380.7
Government securities Non-current |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 336.5 | 245.9
Gross unrealized gains | 0.4 | 0.5
Gross unrealized losses | 0.0 | 0.0
Fair value | 336.9 | 246.4
Mortgage and other asset backed securities Current |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 0.0 | 0.2
Gross unrealized gains | 0.0 | 0.0
Gross unrealized losses | 0.0 | 0.0
Fair value | 0.0 | 0.2
Mortgage and other asset backed securities Non-current |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 128.2 | 122.1
Gross unrealized gains | 0.2 | 0.2
Gross unrealized losses | (0.1) | (0.1)
Fair value | 128.3 | 122.2
Equity Securities, Current |  |
Debt Securities, Available-for-sale [Line Items] |  |
Equity Securities, FV-NI, Cost | 1,168.9 | 70.6
Equity Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 351.0 | 15.9
Equity Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, Before Tax | (77.1) | 0.0
Equity Securities, FV-NI | 1,442.8 | 86.5
Equity Securities, Non-Current |  |
Debt Securities, Available-for-sale [Line Items] |  |
Equity Securities, FV-NI, Cost | 1,168.9 | 1,168.9
Equity Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 351.0 | 733.8
Equity Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, Before Tax | (77.1) | (14.9)
Equity Securities, FV-NI | $ 1,442.8 | $ 1,887.8

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