Financial Instruments (Details 1) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Marketable debt securities
Amortized Cost	$ 3,019.0	$ 2,435.9
Gross unrealized gains	1.4	0.4
Gross unrealized losses	(16.4)	(3.2)
Fair value	3,004.0	2,433.1
Marketable equity securities
Amortized Cost	1,167.0	1,167.0
Gross Unrealized Gains	4.5	160.9
Gross Unrealized Losses	(311.2)	(279.4)
Fair Value	860.3	1,048.5
Corporate debt securities Current
Marketable debt securities
Amortized Cost	1,126.7	723.6
Gross unrealized gains	0.1	0.1
Gross unrealized losses	(2.2)	(0.3)
Fair value	1,124.6	723.4
Corporate debt securities Non-current
Marketable debt securities
Amortized Cost	460.5	385.4
Gross unrealized gains	0.1	0.2
Gross unrealized losses	(5.8)	(0.8)
Fair value	454.8	384.8
Government securities Current
Marketable debt securities
Amortized Cost	878.7	817.0
Gross unrealized gains	1.0	0.0
Gross unrealized losses	(2.6)	(0.4)
Fair value	877.1	816.6
Government securities Non-current
Marketable debt securities
Amortized Cost	379.0	377.0
Gross unrealized gains	0.2	0.1
Gross unrealized losses	(3.6)	(1.0)
Fair value	375.6	376.1
Mortgage and other asset backed securities Current
Marketable debt securities
Amortized Cost	0.7	1.1
Gross unrealized gains	0.0	0.0
Gross unrealized losses	0.0	0.0
Fair value	0.7	1.1
Mortgage and other asset backed securities Non-current
Marketable debt securities
Amortized Cost	173.4	131.8
Gross unrealized gains	0.0	0.0
Gross unrealized losses	(2.2)	(0.7)
Fair value	171.2	131.1
Equity Securities, Current
Marketable equity securities
Amortized Cost	33.9	33.9
Gross Unrealized Gains	0.0	9.9
Gross Unrealized Losses	0.0	0.0
Fair Value	33.9	43.8
Equity Securities, Non-Current
Marketable equity securities
Amortized Cost	1,133.1	1,133.1
Gross Unrealized Gains	4.5	151.0
Gross Unrealized Losses	(311.2)	(279.4)
Fair Value	$ 826.4	$ 1,004.7

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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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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