Nature of the business and basis of presentation (Details) $ / shares in Units, $ in Thousands						3 Months Ended		9 Months Ended
	Aug. 04, 2021 shares	Apr. 28, 2021 USD ($) item $ / shares shares	Oct. 13, 2020 USD ($) $ / shares	Oct. 13, 2020 $ / shares shares	Oct. 06, 2020 $ / shares shares	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Oct. 14, 2021 USD ($)	Oct. 01, 2021 USD ($)	Dec. 31, 2020 USD ($)
Net loss						$ (7,720)	$ (8,377)	$ (16,859)	$ (13,764)
Accumulated deficit						(71,253)		(71,253)				$ (54,394)
Stock issued | shares	14,115
Proceeds from issuance of common stock			$ 41,700					1,338
Payments of underwriting discounts and commissions			$ 3,100
Cash						$ 56,200		$ 56,200
IPO
Stock issued | shares					3,250,000
Share price | $ / shares					$ 12.00
Over-Allotment Option
Stock issued | shares				487,500
Share price | $ / shares			$ 12.00	$ 12.00
Private offering
Share price | $ / shares		$ 27.00
Proceeds from issuance of common stock		$ 27,000
Net proceeds from issuance of common stock		$ 26,400
Number of units issued | shares		1,000,000
Number of share for company's common stock | item		1
Number of warrants | shares		1
Shelf Registration Statement | Subsequent event | Maximum
Securities aggregate price										$ 200,000
Open Market Sale | Subsequent event | Maximum
Securities aggregate price											$ 75,000