Fair value measurement - Financial assets measured at fair value (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2025	Dec. 31, 2024
Maximum
Debt Securities, Available-for-Sale [Line Items]
Contractual maturity term	4 months
Recurring
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 266,608	$ 215,301
Unrealized Gain		57
Unrealized Loss	(24)
Fair Value	266,584	215,358
Recurring \| Level 1 \| Money market funds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	142,424	46,987
Fair Value	142,424	46,987
Recurring \| Level 2 \| U.S. Treasury securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost		94,379
Unrealized Gain		40
Fair Value		94,419
Recurring \| Level 2 \| Marketable securities (U.S. treasury securities)
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	124,184	73,935
Unrealized Gain		17
Unrealized Loss	(24)
Fair Value	$ 124,160	$ 73,952

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) 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, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) 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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Amortized cost 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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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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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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