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Collaboration agreements - Janssen Biotech (Details)	1 Months Ended	3 Months Ended		9 Months Ended
	Feb. 28, 2022 USD ($) target	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)
Collaboration agreements
Collaboration revenue		$ 5,573,000	$ 11,000	$ 11,893,000	$ 32,000
Janssen Agreement
Collaboration agreements
Number of targets designated | target	3
Proceeds from collaborators	$ 40,000,000
Collaboration revenue		4,900,000		10,900,000
Deferred revenue		29,100,000		29,100,000
Remaining performance obligation		29,100,000		29,100,000
Contract assets		$ 0		$ 0
Development, Regulatory & Commercial | Janssen Agreement
Collaboration agreements
Collaboration arrangements, maximum aggregate milestones	505,000,000
Commercial | Janssen Agreement
Collaboration agreements
Collaboration arrangements, maximum aggregate milestones	$ 530,000,000

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