Agreements - Roche (Details) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended
	Jan. 31, 2019	Sep. 30, 2021	Sep. 30, 2020
Collaborative Agreements disclosures
Non-cash royalty revenue related to sale of future royalties		$ 35,035	$ 45,159
Roche
Collaborative Agreements disclosures
Percentage of royalty payments	100.00%
Roche | Kadcyla
Collaborative Agreements disclosures
Non-cash royalty revenue related to sale of future royalties		$ 38,800	$ 45,200
OMERS | Kadcyla
Collaborative Agreements disclosures
Non-cash royalty revenue related to sale of future royalties	$ 65,200
Percentage of royalty payments	100.00%