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Collaborative and Other Relationships - Eisai (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Collaborative arrangements and non-collaborative arrangement transactions
Income (loss) from equity method investments		$ 2.6	$ 34.9	$ 3.3
Eisai
Collaborative arrangements and non-collaborative arrangement transactions
Related cost-sharing reduction (as a percentage)		80.00%
Income (loss) from equity method investments	$ 33.8	$ 0.0	45.0	33.8
Additional milestone payment		$ 0.0	$ 100.0	$ 75.0

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