Available-for-sale debt securities - Schedule of Fair Values Available-For-Sale Debt Securities by Classification (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Location, Statement of Financial Position, Balance [Axis]: us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent
Debt Securities, Available-for-Sale [Line Items]
Fair values of available-for-sale debt securities	$ 666,194	$ 120,097
Location, Statement of Financial Position, Balance [Axis]: us-gaap:CashAndCashEquivalentsAtCarryingValue
Debt Securities, Available-for-Sale [Line Items]
Fair values of available-for-sale debt securities	$ 129,511	$ 20,203

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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+ Details

- 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.

+ References

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