Research Collaboration and License Agreements - Summary of Contract Balances (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Accounts receivable related to collaborations
Beginning balance	$ 1.0	$ 15.0
Additions	1.5	0.0
Payments received	(2.5)	(15.0)
Ending balance	0.0	0.0
Accounts payable related to collaborations
Beginning balance	5.0	0.0
Additions	1.7	0.0
Payments made	(5.0)	0.0
Ending balance	1.7	0.0
Contract assets: Collaboration contract asset
Beginning balance	10.7	12.5
Additions	0.0	0.0
Amortization	(0.6)	(0.4)
Ending balance	10.1	12.1
Contract liabilities: Deferred revenue
Beginning balance	623.7	740.6
Revenue recognized from balances held at the beginning of the period	(31.4)	(24.2)
Additions to collaboration agreements	1.5	3.0
Ending balance	$ 593.8	$ 719.4

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