Basis of Presentation and Summary of Significant Accounting Policies - Revenue by Source (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Total revenues	$ 27,003	$ 24,808	$ 24,987	$ 43,484	$ 59,590	$ 45,663	$ 90,043	$ 56,157	$ 120,282	$ 251,453	$ 141,102
Material sales
Disaggregation of Revenue [Line Items]
Total revenues									31,489	29,123	22,070
License fees, milestones and other revenues
Disaggregation of Revenue [Line Items]
Total revenues									41,817	93,774	30,347
License fees
Disaggregation of Revenue [Line Items]
Total revenues									6,199	78,195	13,665
Milestones
Disaggregation of Revenue [Line Items]
Total revenues									23,451	6,577	11,093
Other
Disaggregation of Revenue [Line Items]
Total revenues									$ 12,167	$ 9,002	$ 5,589