Financial Instruments - Summary of Marketable Securities (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Marketable debt securities:
Amortized Cost	$ 2,199.1	$ 2,435.9
Gross Unrealized Gains	0.3	0.4
Gross Unrealized Losses	(20.2)	(3.2)
Fair Value	2,179.2	2,433.1
Marketable equity securities:
Amortized Cost	1,133.8	1,167.0
Gross Unrealized Gains	0.0	160.9
Gross Unrealized Losses	(342.7)	(279.4)
Fair Value	791.1	1,048.5
Corporate debt securities Current
Marketable debt securities:
Amortized Cost	936.2	723.6
Gross Unrealized Gains	0.0	0.1
Gross Unrealized Losses	(4.9)	(0.3)
Fair Value	931.3	723.4
Corporate debt securities Non-current
Marketable debt securities:
Amortized Cost	305.3	385.4
Gross Unrealized Gains	0.1	0.2
Gross Unrealized Losses	(5.1)	(0.8)
Fair Value	300.3	384.8
Government securities Current
Marketable debt securities:
Amortized Cost	547.1	817.0
Gross Unrealized Gains	0.1	0.0
Gross Unrealized Losses	(5.0)	(0.4)
Fair Value	542.2	816.6
Government securities Non-current
Marketable debt securities:
Amortized Cost	271.4	377.0
Gross Unrealized Gains	0.0	0.1
Gross Unrealized Losses	(3.3)	(1.0)
Fair Value	268.1	376.1
Mortgage and other asset backed securities Current
Marketable debt securities:
Amortized Cost	0.0	1.1
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	0.0	0.0
Fair Value	0.0	1.1
Mortgage and other asset backed securities Non-current
Marketable debt securities:
Amortized Cost	139.1	131.8
Gross Unrealized Gains	0.1	0.0
Gross Unrealized Losses	(1.9)	(0.7)
Fair Value	137.3	131.1
Marketable equity securities, current
Marketable equity securities:
Amortized Cost	1,133.8	33.9
Gross Unrealized Gains	0.0	9.9
Gross Unrealized Losses	(342.7)	0.0
Fair Value	$ 791.1	43.8
Marketable equity securities, non-current
Marketable equity securities:
Amortized Cost		1,133.1
Gross Unrealized Gains		151.0
Gross Unrealized Losses		(279.4)
Fair Value		$ 1,004.7

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