Financial Instruments (Details 1) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Marketable debt securities
Amortized Cost	$ 2,122.7	$ 2,435.9
Gross unrealized gains	0.1	0.4
Gross unrealized losses	(27.0)	(3.2)
Fair value	2,095.8	2,433.1
Marketable equity securities
Amortized Cost	1,133.8	1,167.0
Gross Unrealized Gains	0.0	160.9
Gross Unrealized Losses	(237.8)	(279.4)
Fair Value	896.0	1,048.5
Corporate debt securities Current
Marketable debt securities
Amortized Cost	833.6	723.6
Gross unrealized gains	0.0	0.1
Gross unrealized losses	(6.9)	(0.3)
Fair value	826.7	723.4
Corporate debt securities Non-current
Marketable debt securities
Amortized Cost	400.5	385.4
Gross unrealized gains	0.0	0.2
Gross unrealized losses	(8.1)	(0.8)
Fair value	392.4	384.8
Government securities Current
Marketable debt securities
Amortized Cost	412.1	817.0
Gross unrealized gains	0.1	0.0
Gross unrealized losses	(3.5)	(0.4)
Fair value	408.7	816.6
Government securities Non-current
Marketable debt securities
Amortized Cost	298.8	377.0
Gross unrealized gains	0.0	0.1
Gross unrealized losses	(5.5)	(1.0)
Fair value	293.3	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	177.6	131.8
Gross unrealized gains	0.0	0.0
Gross unrealized losses	(3.0)	(0.7)
Fair value	174.6	131.1
Equity Securities, Current
Marketable equity securities
Amortized Cost		33.9
Gross Unrealized Gains		9.9
Gross Unrealized Losses		0.0
Fair Value		43.8
Equity Securities, Non-Current
Marketable equity securities
Amortized Cost	1,133.8	1,133.1
Gross Unrealized Gains	0.0	151.0
Gross Unrealized Losses	(237.8)	(279.4)
Fair Value	$ 896.0	$ 1,004.7

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