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Financial Instruments (Details 1) - USD ($) $ in Millions | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | $ 2,223.6 | $ 2,049.1
Gross unrealized gains | 1.4 | 2.3
Gross unrealized losses | (1.1) | (0.4)
Fair value | 2,223.9 | 2,051.0
Marketable equity securities, fair value | 2,223.9 | 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 | 1,072.2 | 897.8
Gross unrealized gains | 0.3 | 0.4
Gross unrealized losses | (0.4) | (0.2)
Fair value | 1,072.1 | 898.0
Corporate debt securities Non-current |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 309.9 | 402.5
Gross unrealized gains | 0.6 | 1.1
Gross unrealized losses | (0.1) | (0.1)
Fair value | 310.4 | 403.5
Government securities Current |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 236.5 | 380.6
Gross unrealized gains | 0.1 | 0.1
Gross unrealized losses | 0.0 | 0.0
Fair value | 236.6 | 380.7
Government securities Non-current |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 452.1 | 245.9
Gross unrealized gains | 0.2 | 0.5
Gross unrealized losses | (0.3) | 0.0
Fair value | 452.0 | 246.4
Mortgage and other asset backed securities Current |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 0.2 | 0.2
Gross unrealized gains | 0.0 | 0.0
Gross unrealized losses | 0.0 | 0.0
Fair value | 0.2 | 0.2
Mortgage and other asset backed securities Non-current |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized cost | 152.7 | 122.1
Gross unrealized gains | 0.2 | 0.2
Gross unrealized losses | (0.3) | (0.1)
Fair value | 152.6 | 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 | 607.6 | 15.9
Equity Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, Before Tax | (183.0) | 0.0
Equity Securities, FV-NI | 1,593.5 | 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 | 607.6 | 733.8
Equity Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, Before Tax | (183.0) | (14.9)
Equity Securities, FV-NI | $ 1,593.5 | $ 1,887.8

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