Collaboration, License, and Other Agreements - Schedule of Contract Balances, IO Collaboration (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Accounts receivable, net	$ (4,173.0)	$ (4,114.7)
Sanofi Collaboration Agreement, Immuno-oncology
Disaggregation of Revenue [Line Items]
Accounts receivable, net	(7.4)	(6.5)
Deferred revenue	7.1	10.7
Other liabilities	$ 258.4	$ 280.9

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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