Fair value measurement - Financial assets measured at fair value (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Debt Securities, Available-for-Sale [Line Items]
Fair Value		$ 1,300
Maximum
Debt Securities, Available-for-Sale [Line Items]
Contractual maturity term	11 months
Recurring
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 517,739	652,112
Unrealized Loss	(333)
Fair Value	517,406	652,112
Recurring \| Level 1 \| Money market funds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	159,122	652,112
Fair Value	159,122	$ 652,112
Recurring \| Level 2 \| U.S. Treasury securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	55,994
Fair Value	55,994
Recurring \| Level 2 \| Marketable securities (U.S. treasury securities)
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	302,623
Unrealized Loss	(333)
Fair Value	$ 302,290

Contractual maturity term of debt securities 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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- 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).

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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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