Fair value measurement - Financial assets measured at fair value (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Debt Securities, Available-for-Sale [Line Items]
Unrealized Loss	$ (18)
Contractual maturity term	6 months
Recurring
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 305,565	$ 136,422
Unrealized gain	5	22
Unrealized Loss	(1)
Fair value	305,569	136,444
Recurring \| Level 1 \| Money market funds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	46,482	73,988
Fair value	46,482	73,988
Recurring \| Level 2 \| U.S. Treasury securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	219,101	22,993
Unrealized gain	4
Unrealized Loss	(1)
Fair value	219,104	22,993
Recurring \| Level 2 \| Marketable securities (U.S. treasury securities)
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	39,982	39,441
Unrealized gain	1	22
Fair value	$ 39,983	$ 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).

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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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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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