Collaboration Agreements - Schedule of Contract Balances, IO Collaboration (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Accounts receivable, net	$ 468.3	$ 260.6
Sanofi Collaboration Agreement, Immuno-oncology
Disaggregation of Revenue [Line Items]
Accounts receivable, net	(2.4)	(16.7)
Deferred revenue	12.8	9.4
Other liabilities	$ 527.6	$ 558.6

Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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