Collaboration Agreements - Schedule of Contract Balances, IO Collaboration (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Accounts (payable) receivable	$ 252.0	$ 226.4
Sanofi Collaboration Agreement, Immuno-oncology
Disaggregation of Revenue [Line Items]
Accounts (payable) receivable	(0.8)
Accounts (payable) receivable		77.9
Deferred revenue	$ 629.1	$ 289.9

Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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