v3.25.4
Employee benefit plans - Net pension liability (Details) - EUR (€)
€ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Net defined benefit liability and asset    
Balance at beginning of year € 692,638  
Balance at end of year € 590,684 € 692,638
Weighted average duration of defined benefit obligation 14 years 15 years
United States, France and Germany    
Net defined benefit liability and asset    
Balance at beginning of year € 657,239  
Balance at end of year 554,730 € 657,239
Countries other than US, France, and Germany    
Net defined benefit liability and asset    
Balance at beginning of year 35,399  
Balance at end of year 35,954 35,399
Benefit obligation | United States, France and Germany    
Net defined benefit liability and asset    
Balance at beginning of year 917,071 890,025
Foreign currency translation gains/losses (39,423) 20,472
Current service cost 23,755 28,748
Past service cost (1,678) (481)
(Gains) losses from settlement 216  
Interest expense (income) 37,980 37,304
Transfer of plan participants (1,063) 18
Actuarial (gains) losses arising from changes in financial assumptions (75,217) (19,944)
Actuarial (gains) losses arising from changes in demographic assumptions 5 17
Actuarial (gains) losses arising from experience adjustments (1,572) (185)
Remeasurements (76,784) (20,112)
Benefits paid (36,899) (38,903)
Settlements paid (4,838)  
Balance at end of year 818,337 917,071
Plan assets | United States, France and Germany    
Net defined benefit liability and asset    
Balance at beginning of year (259,832) (255,772)
Foreign currency translation gains/losses 31,103 (15,547)
Interest expense (income) (13,135) (13,169)
Actuarial (gains) losses arising from experience adjustments 4,322 4,122
Actual return on plan assets (8,813) (9,047)
Employer contributions (55,746) (7,968)
Benefits paid 25,059 28,502
Settlements paid 4,622  
Balance at end of year € (263,607) € (259,832)