Operating income - Schedule of operating income (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Other Income and Expenses [Abstract]
Research tax credit	$ 1.6	$ 2.8	$ 3.1	$ 5.0
Total	$ 1.6	$ 2.8	$ 3.1	$ 5.0

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details