Collaboration, License, and Other Agreements - Summary (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues:
Revenue	$ 117,130	$ 103,747	$ 104,031	$ 88,845	$ 116,680	$ 103,468	$ 89,432	$ 79,943	$ 413,753	$ 389,523	$ 428,413
Collaborative arrangements revenue
Revenues:
Revenue									412,784	381,545	379,652
Collaborative arrangement, other agreements
Revenues:
Revenue									1,755	1,335	1,845
Sale of active pharmaceutical ingredient
Revenues:
Revenue									969	7,978	48,761
AbbVie | Collaborative arrangement, co-promotion agreements
Revenues:
Revenue											3,723
AbbVie | Sale of active pharmaceutical ingredient
Revenues:
Revenue									223	421
AbbVie | North America | Collaborative arrangements revenue
Revenues:
Revenue									403,085	370,902	327,591
AbbVie | North America | Collaborative arrangement, collaboration and license agreements
Revenues:
Revenue									403,085	370,902	327,591
AbbVie | Europe and Other | Collaborative arrangement, collaboration and license agreements
Revenues:
Revenue									2,558	2,196	1,718
AstraZeneca | Collaborative arrangement, collaboration and license agreements
Revenues:
Revenue									743	682	32,628
AstraZeneca | Sale of active pharmaceutical ingredient
Revenues:
Revenue									597	5,540	2,973
Astellas Pharma Inc. | Collaborative arrangement, collaboration and license agreements
Revenues:
Revenue									2,232	2,128	10,147
Astellas Pharma Inc. | Sale of active pharmaceutical ingredient
Revenues:
Revenue									149	2,017	45,788
Alnylam | Collaborative arrangement, co-promotion agreements
Revenues:
Revenue									$ 2,411	$ 4,302	$ 2,000