Summary of significant accounting policies - Narrative (Details)		12 Months Ended
	Sep. 02, 2022 USD ($) $ / shares	Dec. 31, 2022 USD ($) segment	Dec. 31, 2021 USD ($)	Mar. 10, 2023 USD ($)	Sep. 30, 2022 $ / shares	Sep. 01, 2022 $ / shares	Jan. 01, 2022 USD ($)
Summary of significant accounting policies
Number of operating segments | segment		1
Restricted cash		$ 100,000	$ 100,000
Deferred offering costs		300,000	300,000
Operating lease liability							$ 500,000
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]							Accrued Liabilities and Other Liabilities
Operating right-of-use asset, net		$ 284,000					$ 500,000
Expected dividend yield		0.00%
Impairment losses		$ 0	$ 0
Deemed dividend	$ 600,000	$ 622,000
Impact of deemed dividend in stockholder' equity	$ 0
SVB [Member] | Subsequent events
Summary of significant accounting policies
Losses On Deposits				$ 0
Series B Warrants
Summary of significant accounting policies
Exercise price | $ / shares	$ 10.00				$ 10.00	$ 45.00