Revenues - Summary of Revenues by Collaboration, Category of Revenue and Method of Recognition (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
License And Collaboration Agreements [Line Items]
Total revenues	$ 112	$ 383	$ 78
Gilead Collaboration License to Domvanalimab
License And Collaboration Agreements [Line Items]
Total revenues		329
Gilead Collaboration, License to Zimberelimab
License And Collaboration Agreements [Line Items]
Total revenues			55
Gilead Collaboration, License and R&D services
License And Collaboration Agreements [Line Items]
Total revenues	74	1
Gilead Collaboration, Access Rights
License And Collaboration Agreements [Line Items]
Total revenues	33	31	16
Taiho Collaboration, License to Domvanalimab
License And Collaboration Agreements [Line Items]
Total revenues		15
Taiho Collaboration, Access Rights
License And Collaboration Agreements [Line Items]
Total revenues	$ 5	$ 7	$ 7