Collaborative Arrangements and Acquisitions - Aggregate VIE Financial Information, Increase in the fair value of contingent payments (Details) - Variable Interest Entity, Primary Beneficiary - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Decrease (increase) in fair value of contingent payments	$ (200)	$ 69,550	$ (23,100)	$ 62,560
Parion Sciences, Inc.
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Decrease (increase) in fair value of contingent payments	0	69,550	0	63,460
BioAxone Biosciences Inc.
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Decrease (increase) in fair value of contingent payments	$ (200)	$ 0	$ (23,100)	$ (900)