Employee benefits - Narrative (Details)	12 Months Ended
Dec. 31, 2025 EUR (€) Person Company Plan Rate	Dec. 31, 2024 EUR (€) Rate	Dec. 31, 2023 EUR (€) Rate
Defined Benefit Plan Disclosure [Line Items]
Number of plans \| Plan	1
Multiemployer plan and defined contribution costs, employer contribution, accrued premium	€ 75,800,000	€ 75,900,000
Cymer compensation plan deferral period	3 years
Cymer compensation plan expenses	€ 0	0	€ 0
Deferred compensation plan liability	127,700,000	111,800,000
Compensation plan assets	€ 129,900,000	€ 113,100,000
Netherlands multi-employer union plan
Defined Benefit Plan Disclosure [Line Items]
Number of full time equivalent employees in multiemployer union plans \| Person	23,711
Number of full time equivalent employees in multiemployer union plans (in percentage)	54.50%
Number of companies covered by multiemployer plan \| Company	1,618
Number of employees covered \| Person	184,847
Employer contributions percentage \| Rate	28.00%	28.00%	28.00%
Employer contribution under CBA, percentage \| Rate	19.50%	18.20%	18.30%
Multi-employer union plan expected contribution	€ 437,000,000.0
Minimal coverage ratio (in percentage)	1.043	1.043
Multiemployer plan coverage ratio \| Rate	125.30%	113.10%
Netherlands multi-employer union plan \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Multiemployer plan coverage ratio \| Rate	118.10%

In July 2002, we adopted a non-qualified deferred compensation plan for our US employees that allows a select group of management or highly compensated employees to defer a portion of their salary, bonus, and commissions. The plan allows us to credit additional amounts to the participants’ account balances. The participants divide their funds among the investments available in the plan. Participants elect to receive their funds in future periods after the earlier of their employment termination or their withdrawal election, at least 3 years after deferral.

No definition available.