Financial Instruments (Details 1) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Marketable debt securities
Amortized Cost	$ 3,133.9	$ 2,199.1
Gross unrealized gains	2.3	0.3
Gross unrealized losses	(14.9)	(20.2)
Fair value	3,121.3	2,179.2
Marketable equity securities
Amortized Cost	1,088.8	1,133.8
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(410.7)	(342.7)
Fair Value	678.1	791.1
Corporate debt securities Current
Marketable debt securities
Amortized Cost	1,287.6	936.2
Gross unrealized gains	0.1	0.0
Gross unrealized losses	(4.4)	(4.9)
Fair value	1,283.3	931.3
Corporate debt securities Non-current
Marketable debt securities
Amortized Cost	423.4	305.3
Gross unrealized gains	1.0	0.1
Gross unrealized losses	(3.5)	(5.1)
Fair value	420.9	300.3
Government securities Current
Marketable debt securities
Amortized Cost	863.5	547.1
Gross unrealized gains	0.1	0.1
Gross unrealized losses	(4.2)	(5.0)
Fair value	859.4	542.2
Government securities Non-current
Marketable debt securities
Amortized Cost	426.1	271.4
Gross unrealized gains	1.0	0.0
Gross unrealized losses	(1.5)	(3.3)
Fair value	425.6	268.1
Mortgage and other asset backed securities Current
Marketable debt securities
Amortized Cost	0.4	0.0
Gross unrealized gains	0.0	0.0
Gross unrealized losses	0.0	0.0
Fair value	0.4	0.0
Mortgage and other asset backed securities Non-current
Marketable debt securities
Amortized Cost	132.9	139.1
Gross unrealized gains	0.1	0.1
Gross unrealized losses	(1.3)	(1.9)
Fair value	131.7	137.3
Equity Securities, Current
Marketable equity securities
Amortized Cost	87.7	1,133.8
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(19.8)	(342.7)
Fair Value	67.9	$ 791.1
Equity Securities, Non-Current
Marketable equity securities
Amortized Cost	1,001.1
Gross Unrealized Gains	0.0
Gross Unrealized Losses	(390.9)
Fair Value	$ 610.2

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