Fair value measurement - Financial assets measured at fair value (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2024	Sep. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale [Line Items]
Unrealized Gain	$ 68	$ 48
Maximum
Debt Securities, Available-for-Sale [Line Items]
Contractual maturity term		6 months
Recurring
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	237,150	$ 237,150	$ 136,422
Unrealized Gain		70	22
Fair Value	237,220	237,220	136,444
Recurring \| Level 1 \| Money market funds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	72,878	72,878	73,988
Fair Value	72,878	72,878	73,988
Recurring \| Level 2 \| U.S. Treasury securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	79,760	79,760	22,993
Unrealized Gain		20
Fair Value	79,780	79,780	22,993
Recurring \| Level 2 \| Marketable securities (U.S. treasury securities)
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	84,512	84,512	39,441
Unrealized Gain		50	22
Fair Value	$ 84,562	$ 84,562	$ 39,463

Contractual maturity term of debt securities available for sale.

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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

No definition available.

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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 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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