Collaborative Research and Development Agreements - Schedule of Milestone Achieved (Details) - USD ($) $ in Thousands	3 Months Ended														12 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Sep. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue															$ 10,287	$ 63,175	$ 75,000
GSK
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue															10,300	$ 63,200
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | Initiated in vivo toxicology studies using good laboratory practices (GLPs)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue														$ 1,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | IND clearance from the FDA
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue												$ 4,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | Phase 2 clinical trial initiation
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue									$ 3,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | Phase 3 clinical trial initiation - first indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue							$ 5,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | Phase 3 clinical trial initiation - second indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue						$ 5,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | Filing of the first BLA - first indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue				$ 10,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | Filing of the first MAA - first indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue				$ 5,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | Filing of the first BLA - second indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue			$ 10,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | First BLA approval - first indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue		$ 20,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | First MAA approval - first indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue		$ 10,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | First BLA approval - second indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue	$ 20,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | Filing of the first MAA - second indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															5,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | First MAA approval - second indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															10,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | First commercial sales milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															15,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | Second commercial sales milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															25,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | Third commercial sales milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															50,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | Fourth commercial sales milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															75,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | Milestones recognized through December 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue															93,000
GSK | Anti-PD-1 (JEMPERLI/Dostarlimab) | Milestones that may be recognized in the future
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															180,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Initiated in vivo toxicology studies using good laboratory practices (GLPs)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue													$ 1,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | IND clearance from the FDA
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue											$ 4,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Phase 2 clinical trial initiation
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue								$ 3,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Phase 3 clinical trial initiation - first indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue															5,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Phase 3 clinical trial initiation - second indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															5,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Filing of the first BLA - first indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															10,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Filing of the first MAA - first indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															5,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Filing of the first BLA - second indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															10,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | First BLA approval - first indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															20,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | First MAA approval - first indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															10,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | First BLA approval - second indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															20,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Filing of the first MAA - second indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															5,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | First MAA approval - second indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															10,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | First commercial sales milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															15,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Second commercial sales milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															25,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Third commercial sales milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															50,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Fourth commercial sales milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															75,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Milestones recognized through December 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue															13,000
GSK | Anti-TIM-3 (GSK4069889A/Cobolimab) | Milestones that may be recognized in the future
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															260,000
GSK | Anti-LAG-3 (GSK40974386) | Initiated in vivo toxicology studies using good laboratory practices (GLPs)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue										$ 1,000
GSK | Anti-LAG-3 (GSK40974386) | IND clearance from the FDA
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue									$ 4,000
GSK | Anti-LAG-3 (GSK40974386) | Phase 2 clinical trial initiation
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue					$ 3,000
GSK | Anti-LAG-3 (GSK40974386) | Phase 3 clinical trial initiation - first indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															5,000
GSK | Anti-LAG-3 (GSK40974386) | Phase 3 clinical trial initiation - second indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															5,000
GSK | Anti-LAG-3 (GSK40974386) | Filing of the first BLA - first indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															10,000
GSK | Anti-LAG-3 (GSK40974386) | Filing of the first MAA - first indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															5,000
GSK | Anti-LAG-3 (GSK40974386) | Filing of the first BLA - second indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															10,000
GSK | Anti-LAG-3 (GSK40974386) | First BLA approval - first indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															20,000
GSK | Anti-LAG-3 (GSK40974386) | First MAA approval - first indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															10,000
GSK | Anti-LAG-3 (GSK40974386) | First BLA approval - second indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															20,000
GSK | Anti-LAG-3 (GSK40974386) | Filing of the first MAA - second indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															5,000
GSK | Anti-LAG-3 (GSK40974386) | First MAA approval - second indication
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															10,000
GSK | Anti-LAG-3 (GSK40974386) | First commercial sales milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															15,000
GSK | Anti-LAG-3 (GSK40974386) | Second commercial sales milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															25,000
GSK | Anti-LAG-3 (GSK40974386) | Third commercial sales milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															50,000
GSK | Anti-LAG-3 (GSK40974386) | Fourth commercial sales milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															75,000
GSK | Anti-LAG-3 (GSK40974386) | Milestones recognized through December 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration revenue															8,000
GSK | Anti-LAG-3 (GSK40974386) | Milestones that may be recognized in the future
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestones that may be recognized in the future															$ 265,000