Government assistance programs (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Jul. 31, 2020	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021	May 31, 2021	Mar. 27, 2020
Unusual or Infrequent Item, or Both [Line Items]
Contra-research and development expense				$ 600
Refundable employee retention credit								$ 800
Contra General And Administrative Expense				200
Contra expenses		$ 0	$ 0		$ 0
Employee retention credit receivable		847		847		$ 0
Other Transaction Authority for Prototype Agreement
Unusual or Infrequent Item, or Both [Line Items]
Grants Receivable	$ 13,300						$ 17,600
Payment period of reimbursement contract	30 days
Contra-research and development expense		0	$ 5,300	600	$ 13,400
Prepaid expenses and other current assets		200		200		2,700
Deferred research obligation liability		0		0		2,000
Grant expected to be received		$ 0		0		$ 1,600
Reimbursement expenses received				$ 17,400