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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Collaboration agreements - Merck KGaA - Accounting Analysis (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022 USD ($) target	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Collaboration agreements
Collaboration revenue	$ 2,036	$ 11
Research and development	35,806	27,415
Merck KGaA Agreement and Merck KGaA Supply Agreement
Collaboration agreements
Deferred revenue	$ 3,900		$ 3,900
Merck KGaA
Collaboration agreements
Number of targets with satisfied performance obligations \| target	4
Deferred revenue	$ 3,933	3,976	$ 3,944	$ 3,987
Merck KGaA Supply Agreement
Collaboration agreements
Research and development	$ 0	$ 0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-04-01 \| Merck KGaA \| Rights to future technological improvements
Collaboration agreements
Expected recognition period	10 years
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-04-01 \| Merck KGaA \| Joint research committee services
Collaboration agreements
Expected recognition period	5 years