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Financial Instruments (Details 1) - USD ($) $ in Millions | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Marketable equity securities |  |
Amortized Cost | $ 734.3 | $ 979.9
Gross Unrealized Gains | 0.0 | 0.0
Gross Unrealized Losses | (429.6) | (563.1)
Fair Value | 304.7 | 416.8
Equity Securities, Current |  |
Marketable equity securities |  |
Amortized Cost | 58.3 | 31.6
Gross Unrealized Gains | 0.0 | 0.0
Gross Unrealized Losses | (8.2) | (21.0)
Fair Value | 50.1 | 10.6
Equity Securities, Non-Current |  |
Marketable equity securities |  |
Amortized Cost | 676.0 | 948.3
Gross Unrealized Gains | 0.0 | 0.0
Gross Unrealized Losses | (421.4) | (542.1)
Fair Value | $ 254.6 | $ 406.2

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