Financial Instruments (Details 1) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Marketable debt securities
Amortized Cost	$ 3,279.6	$ 2,435.9
Gross unrealized gains	0.4	0.4
Gross unrealized losses	(25.8)	(3.2)
Fair value	3,254.2	2,433.1
Marketable equity securities
Amortized Cost	1,137.2	1,167.0
Gross Unrealized Gains	0.0	160.9
Gross Unrealized Losses	(351.6)	(279.4)
Fair Value	785.6	1,048.5
Corporate debt securities Current
Marketable debt securities
Amortized Cost	1,363.9	723.6
Gross unrealized gains	0.0	0.1
Gross unrealized losses	(6.3)	(0.3)
Fair value	1,357.6	723.4
Corporate debt securities Non-current
Marketable debt securities
Amortized Cost	540.4	385.4
Gross unrealized gains	0.1	0.2
Gross unrealized losses	(7.8)	(0.8)
Fair value	532.7	384.8
Government securities Current
Marketable debt securities
Amortized Cost	798.0	817.0
Gross unrealized gains	0.1	0.0
Gross unrealized losses	(4.5)	(0.4)
Fair value	793.6	816.6
Government securities Non-current
Marketable debt securities
Amortized Cost	367.2	377.0
Gross unrealized gains	0.2	0.1
Gross unrealized losses	(4.1)	(1.0)
Fair value	363.3	376.1
Mortgage and other asset backed securities Current
Marketable debt securities
Amortized Cost	0.1	1.1
Gross unrealized gains	0.0	0.0
Gross unrealized losses	0.0	0.0
Fair value	0.1	1.1
Mortgage and other asset backed securities Non-current
Marketable debt securities
Amortized Cost	210.0	131.8
Gross unrealized gains	0.0	0.0
Gross unrealized losses	(3.1)	(0.7)
Fair value	206.9	131.1
Equity Securities, Current
Marketable equity securities
Amortized Cost	33.9	33.9
Gross Unrealized Gains	0.0	9.9
Gross Unrealized Losses	9.7	0.0
Fair Value	24.2	43.8
Equity Securities, Non-Current
Marketable equity securities
Amortized Cost	1,103.3	1,133.1
Gross Unrealized Gains	0.0	151.0
Gross Unrealized Losses	(341.9)	(279.4)
Fair Value	$ 761.4	$ 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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