Fair value measurement - Financial assets measured at fair value (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Dec. 31, 2024
Maximum
Debt Securities, Available-for-Sale [Line Items]
Contractual maturity term	6 months
Recurring
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 315,652	$ 215,301
Unrealized Gain		57
Unrealized Loss	(3)
Fair Value	315,649	215,358
Recurring \| Level 1 \| Money market funds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	255,939	46,987
Fair Value	255,939	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	59,713	73,935
Unrealized Gain		17
Unrealized Loss	(3)
Fair Value	$ 59,710	$ 73,952

Contractual maturity term of debt securities available for sale.

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

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).

+ References

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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- 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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