Government assistance programs (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended	12 Months Ended
	Jan. 31, 2023	Jul. 31, 2020	Mar. 31, 2022	Dec. 31, 2022	Mar. 31, 2023	May 31, 2020	Mar. 27, 2020
Unusual or Infrequent Item, or Both [Line Items]
Contra-research and development expense			$ 600
Refundable employee retention credit							$ 800
Employee retention credit receivable				$ 847	$ 821
Other Transaction Authority for Prototype Agreement
Unusual or Infrequent Item, or Both [Line Items]
Grants Receivable		$ 13,300				$ 17,600
Expenses relating to extension of an agreement	$ 0
Payment period of reimbursement contract		30 days
Reimbursement expenses received				$ 17,600