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Financial Instruments - Summary of Marketable Securities (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Marketable debt securities: |  |
Amortized Cost | $ 2,199.1 | $ 2,435.9
Gross Unrealized Gains | 0.3 | 0.4
Gross Unrealized Losses | (20.2) | (3.2)
Fair Value | 2,179.2 | 2,433.1
Marketable equity securities: |  |
Amortized Cost | 1,133.8 | 1,167.0
Gross Unrealized Gains | 0.0 | 160.9
Gross Unrealized Losses | (342.7) | (279.4)
Fair Value | 791.1 | 1,048.5
Corporate debt securities Current |  |
Marketable debt securities: |  |
Amortized Cost | 936.2 | 723.6
Gross Unrealized Gains | 0.0 | 0.1
Gross Unrealized Losses | (4.9) | (0.3)
Fair Value | 931.3 | 723.4
Corporate debt securities Non-current |  |
Marketable debt securities: |  |
Amortized Cost | 305.3 | 385.4
Gross Unrealized Gains | 0.1 | 0.2
Gross Unrealized Losses | (5.1) | (0.8)
Fair Value | 300.3 | 384.8
Government securities Current |  |
Marketable debt securities: |  |
Amortized Cost | 547.1 | 817.0
Gross Unrealized Gains | 0.1 | 0.0
Gross Unrealized Losses | (5.0) | (0.4)
Fair Value | 542.2 | 816.6
Government securities Non-current |  |
Marketable debt securities: |  |
Amortized Cost | 271.4 | 377.0
Gross Unrealized Gains | 0.0 | 0.1
Gross Unrealized Losses | (3.3) | (1.0)
Fair Value | 268.1 | 376.1
Mortgage and other asset backed securities Current |  |
Marketable debt securities: |  |
Amortized Cost | 0.0 | 1.1
Gross Unrealized Gains | 0.0 | 0.0
Gross Unrealized Losses | 0.0 | 0.0
Fair Value | 0.0 | 1.1
Mortgage and other asset backed securities Non-current |  |
Marketable debt securities: |  |
Amortized Cost | 139.1 | 131.8
Gross Unrealized Gains | 0.1 | 0.0
Gross Unrealized Losses | (1.9) | (0.7)
Fair Value | 137.3 | 131.1
Marketable equity securities, current |  |
Marketable equity securities: |  |
Amortized Cost | 1,133.8 | 33.9
Gross Unrealized Gains | 0.0 | 9.9
Gross Unrealized Losses | (342.7) | 0.0
Fair Value | $ 791.1 | 43.8
Marketable equity securities, non-current |  |
Marketable equity securities: |  |
Amortized Cost |  | 1,133.1
Gross Unrealized Gains |  | 151.0
Gross Unrealized Losses |  | (279.4)
Fair Value |  | $ 1,004.7

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