Financial Instruments (Details 1) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Marketable debt securities
Amortized Cost		$ 2,199.1
Gross unrealized gains		0.3
Gross unrealized losses		(20.2)
Fair value		2,179.2
Marketable equity securities
Amortized Cost	$ 993.3	1,133.8
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(579.7)	(342.7)
Fair Value	413.6	791.1
Corporate debt securities Current
Marketable debt securities
Amortized Cost		936.2
Gross unrealized gains		0.0
Gross unrealized losses		(4.9)
Fair value		931.3
Corporate debt securities Non-current
Marketable debt securities
Amortized Cost		305.3
Gross unrealized gains		0.1
Gross unrealized losses		(5.1)
Fair value		300.3
Government securities Current
Marketable debt securities
Amortized Cost		547.1
Gross unrealized gains		0.1
Gross unrealized losses		(5.0)
Fair value		542.2
Government securities Non-current
Marketable debt securities
Amortized Cost		271.4
Gross unrealized gains		0.0
Gross unrealized losses		(3.3)
Fair value		268.1
Mortgage and other asset backed securities Current
Marketable debt securities
Amortized Cost		0.0
Gross unrealized gains		0.0
Gross unrealized losses		0.0
Fair value		0.0
Mortgage and other asset backed securities Non-current
Marketable debt securities
Amortized Cost		139.1
Gross unrealized gains		0.1
Gross unrealized losses		(1.9)
Fair value		137.3
Equity Securities, Current
Marketable equity securities
Amortized Cost		1,133.8
Gross Unrealized Gains		0.0
Gross Unrealized Losses		(342.7)
Fair Value		$ 791.1
Equity Securities, Non-Current
Marketable equity securities
Amortized Cost	993.3
Gross Unrealized Gains	0.0
Gross Unrealized Losses	(579.7)
Fair Value	$ 413.6

Equity Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax

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Equity Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, Before Tax

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

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