Marketable Securities - Schedule of Investments in Available For Sale Debt Securities (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	$ 8,428.7	$ 3,649.2
Unrealized Gains	10.8	40.1
Unrealized Losses	(42.3)	(0.2)
Fair Value	8,397.2	3,689.1
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	7,518.4	3,053.0
Unrealized Gains	10.2	37.5
Unrealized Losses	(40.9)	(0.2)
Fair Value	7,487.7	3,090.3
U.S. government and government agency obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	109.0	127.6
Unrealized Gains	0.3	1.3
Unrealized Losses	(0.8)	0.0
Fair Value	108.5	128.9
Sovereign bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	64.4	65.2
Unrealized Gains	0.3	1.1
Unrealized Losses	(0.3)	0.0
Fair Value	64.4	66.3
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	439.7	276.0
Unrealized Gains	0.0	0.1
Unrealized Losses	(0.1)	0.0
Fair Value	439.6	276.1
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	255.2	127.4
Unrealized Gains	0.0	0.1
Unrealized Losses	(0.1)	0.0
Fair Value	255.1	$ 127.5
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	42.0
Unrealized Gains	0.0
Unrealized Losses	(0.1)
Fair Value	$ 41.9