Financial Instruments (Details 1) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Marketable debt securities
Amortized Cost	$ 4,686.8	$ 2,199.1
Gross unrealized gains	1.1	0.3
Gross unrealized losses	(19.4)	(20.2)
Fair value	4,668.5	2,179.2
Marketable equity securities
Amortized Cost	1,001.1	1,133.8
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(284.1)	(342.7)
Fair Value	717.0	791.1
Corporate debt securities Current
Marketable debt securities
Amortized Cost	1,363.9	936.2
Gross unrealized gains	0.1	0.0
Gross unrealized losses	(4.0)	(4.9)
Fair value	1,360.0	931.3
Corporate debt securities Non-current
Marketable debt securities
Amortized Cost	475.2	305.3
Gross unrealized gains	0.3	0.1
Gross unrealized losses	(4.5)	(5.1)
Fair value	471.0	300.3
Government securities Current
Marketable debt securities
Amortized Cost	2,104.3	547.1
Gross unrealized gains	0.4	0.1
Gross unrealized losses	(4.2)	(5.0)
Fair value	2,100.5	542.2
Government securities Non-current
Marketable debt securities
Amortized Cost	555.3	271.4
Gross unrealized gains	0.1	0.0
Gross unrealized losses	(5.6)	(3.3)
Fair value	549.8	268.1
Mortgage and other asset backed securities Current
Marketable debt securities
Amortized Cost	0.0	0.0
Gross unrealized gains	0.0	0.0
Gross unrealized losses	0.0	0.0
Fair value	0.0	0.0
Mortgage and other asset backed securities Non-current
Marketable debt securities
Amortized Cost	188.1	139.1
Gross unrealized gains	0.2	0.1
Gross unrealized losses	(1.1)	(1.9)
Fair value	187.2	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	1,001.1
Gross Unrealized Gains	0.0
Gross Unrealized Losses	(284.1)
Fair Value	$ 717.0

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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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