Fair value measurement - Financial assets measured at fair value (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale [Line Items]
Unrealized Loss	$ (2)	$ (20)
Maximum
Debt Securities, Available-for-Sale [Line Items]
Contractual maturity term		6 months
Recurring
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	276,461	$ 276,461	$ 136,422
Unrealized gain		4	22
Unrealized Loss		(2)
Fair value	276,463	276,463	136,444
Recurring \| Level 1 \| Money market funds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	24,259	24,259	73,988
Fair value	24,259	24,259	73,988
Recurring \| Level 2 \| U.S. Treasury securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	139,183	139,183	22,993
Unrealized gain		1
Unrealized Loss		(1)
Fair value	139,183	139,183	22,993
Recurring \| Level 2 \| Marketable securities (U.S. treasury securities)
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	113,019	113,019	39,441
Unrealized gain		3	22
Unrealized Loss		(1)
Fair value	$ 113,021	$ 113,021	$ 39,463

Contractual maturity term of debt securities available for sale.

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- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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- Definition

Amount of unrealized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Amount of unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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