Summary of significant accounting policies (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities	$ 392,221		$ 396,444
Unrealized gains on marketable securities	1,776	$ 5,469
Fair value, recurring \| Money market funds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Assets at fair value	$ 353,000		$ 366,800

Fair value portion of asset recognized for present right to economic benefit.

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