Cash, cash equivalents, restricted cash and available-for-sale marketable securities - Cash, cash equivalents, and marketable securities (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Amortized Cost
Cash and cash equivalents	$ 65,269	$ 98,959
Total money market funds and marketable securities	245,885	111,704
Debt securities, unrealized loss position	81,800	19,900
Fair Value
Total money market funds and marketable securities	245,764	111,613
Unrealized Gains and Losses
Marketable securities, unrealized gains	3
Marketable securities, unrealized losses	$ (124)	(91)
Maximum
Amortized Cost
Debt securities, contractual maturity period	1 year
Money market funds
Amortized Cost
Cash and cash equivalents	$ 58,098	91,724
Fair Value
Cash and cash equivalents	58,098	91,724
U.S. Treasury notes
Amortized Cost
Marketable securities, amortized cost	111,120	19,980
Fair Value
Marketable securities, fair value	111,071	19,889
Unrealized Gains and Losses
Marketable securities, unrealized gains	3
Marketable securities, unrealized losses	(52)	$ (91)
U. S. Government agency securities
Amortized Cost
Marketable securities, amortized cost	34,273
Fair Value
Marketable securities, fair value	34,232
Unrealized Gains and Losses
Marketable securities, unrealized losses	(41)
Corporate bonds
Amortized Cost
Marketable securities, amortized cost	27,811
Fair Value
Marketable securities, fair value	27,780
Unrealized Gains and Losses
Marketable securities, unrealized losses	(31)
Commercial paper
Amortized Cost
Marketable securities, amortized cost	14,583
Fair Value
Marketable securities, fair value	$ 14,583