Collaborative Arrangements and Acquisitions - BioAxone Biosciences, Inc. (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Net loss (income) attributable to noncontrolling interest	$ 0	$ 290	$ 0	$ (15,638)
Increase in fair value of contingent payments	2,959	0	2,959	0
Provision for income taxes	$ 13,148	8,055	$ 124,393	5,737
BioAxone Biosciences Inc.
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Increase in fair value of contingent payments				24,000
Collaborative arrangement, up-front payment		$ 10,000
Provision for income taxes				$ 6,000

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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The amount of the up-front license fee paid by the entity pursuant to a collaborative arrangement.

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