Fair value measurements - Fair Value, Assets Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Assets, Fair Value Disclosure [Abstract]
Short-term marketable securities	$ 157,856	$ 151,827
U.S. treasury securities
Assets, Fair Value Disclosure [Abstract]
Short-term marketable securities	83,362	107,810
U.S. government agency securities
Assets, Fair Value Disclosure [Abstract]
Short-term marketable securities	74,494	44,017
Recurring basis
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	57,095	60,464
Short-term marketable securities	157,856	151,827
Recurring basis | Money market funds
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	52,105	50,471
Recurring basis | U.S. treasury securities
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	4,990
Short-term marketable securities	83,362	107,810
Recurring basis | U.S. government agency securities
Assets, Fair Value Disclosure [Abstract]
Cash equivalents		9,993
Short-term marketable securities	74,494	44,017
Recurring basis | Quoted Prices in Active Markets (Level 1)
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	57,095	50,471
Short-term marketable securities	83,362	107,810
Recurring basis | Quoted Prices in Active Markets (Level 1) | Money market funds
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	52,105	50,471
Recurring basis | Quoted Prices in Active Markets (Level 1) | U.S. treasury securities
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	4,990
Short-term marketable securities	83,362	107,810
Recurring basis | Quoted Prices in Active Markets (Level 1) | U.S. government agency securities
Assets, Fair Value Disclosure [Abstract]
Cash equivalents		0
Short-term marketable securities	0	0
Recurring basis | Significant Other Observable Inputs (Level 2)
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	0	9,993
Short-term marketable securities	74,494	44,017
Recurring basis | Significant Other Observable Inputs (Level 2) | Money market funds
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	0	0
Recurring basis | Significant Other Observable Inputs (Level 2) | U.S. treasury securities
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	0
Short-term marketable securities	0	0
Recurring basis | Significant Other Observable Inputs (Level 2) | U.S. government agency securities
Assets, Fair Value Disclosure [Abstract]
Cash equivalents		9,993
Short-term marketable securities	74,494	44,017
Recurring basis | Significant Unobservable Inputs (Level 3)
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	0	0
Short-term marketable securities	0	0
Recurring basis | Significant Unobservable Inputs (Level 3) | Money market funds
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	0	0
Recurring basis | Significant Unobservable Inputs (Level 3) | U.S. treasury securities
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	0
Short-term marketable securities	0	0
Recurring basis | Significant Unobservable Inputs (Level 3) | U.S. government agency securities
Assets, Fair Value Disclosure [Abstract]
Cash equivalents		0
Short-term marketable securities	$ 0	$ 0