v3.25.4
Share-based compensation - Restricted shares (Detail) - Restricted shares
 12 Months Ended
Dec. 31, 2025
shares
€ / shares
Dec. 31, 2025
shares
$ / shares
Dec. 31, 2024
shares
€ / shares
Dec. 31, 2024
shares
$ / shares
EUR-denominated        
Share-based compensation [Line Items]        
Number of other equity instruments outstanding in share-based payment arrangement at beginning of period (in shares) 3,523,906 3,523,906 2,995,252 2,995,252
Weighted average exercise price of other equity instruments outstanding in share-based payment arrangement at beginning of period (in euros per share) | € / shares € 21.17   € 23.39  
Number of other equity instruments granted in share-based payment arrangement (in shares) 1,146,201 1,146,201 1,367,380 1,367,380
Weighted average exercise price of other equity instruments granted in share-based payment arrangement (in euros per share) | € / shares € 19.38   € 22.64  
Notional Dividends (in shares) 145,617 145,617 52,481 52,481
Weighted average exercise price notional dividends (in euros per share) | € / shares € 21.43   € 22.57  
Number of other equity instruments exercised or vested in share-based payment arrangement (in shares) (1,147,752) (1,147,752) (627,855) (627,855)
Weighted average exercise price of other equity instruments exercised or vested in share-based payment arrangement (in euros per share) | € / shares € 21.70   € 35.10  
Number of other equity instruments forfeited in share-based payment arrangement (in shares) (244,654) (244,654) (263,352) (263,352)
Weighted average exercise price of other equity instruments forfeited in share-based payment arrangement (in euros per share) | € / shares € 20.65   € 21.06  
Number of other equity instruments outstanding in share-based payment arrangement at end of period (in shares) 3,423,318 3,423,318 3,523,906 3,523,906
Weighted average exercise price of other equity instruments outstanding in share-based payment arrangement at end of period (in euros per share) | € / shares € 20.44   € 21.17  
US Dollar        
Share-based compensation [Line Items]        
Number of other equity instruments outstanding in share-based payment arrangement at beginning of period (in shares) 3,327,230 3,327,230 2,654,193 2,654,193
Weighted average exercise price of other equity instruments outstanding in share-based payment arrangement at beginning of period (in euros per share) | $ / shares   $ 23.04   $ 26.04
Number of other equity instruments granted in share-based payment arrangement (in shares) 1,118,263 1,118,263 1,460,620 1,460,620
Weighted average exercise price of other equity instruments granted in share-based payment arrangement (in euros per share) | $ / shares   $ 22.18   $ 24.59
Notional Dividends (in shares) 136,697 136,697 48,774 48,774
Weighted average exercise price notional dividends (in euros per share) | $ / shares   $ 22.66   $ 24.33
Number of other equity instruments exercised or vested in share-based payment arrangement (in shares) (1,070,835) (1,070,835) (582,404) (582,404)
Weighted average exercise price of other equity instruments exercised or vested in share-based payment arrangement (in euros per share) | $ / shares   $ 23.24   $ 40.51
Number of other equity instruments forfeited in share-based payment arrangement (in shares) (341,996) (341,996) (253,953) (253,953)
Weighted average exercise price of other equity instruments forfeited in share-based payment arrangement (in euros per share) | $ / shares   $ 22.97   $ 23.43
Number of other equity instruments outstanding in share-based payment arrangement at end of period (in shares) 3,169,359 3,169,359 3,327,230 3,327,230
Weighted average exercise price of other equity instruments outstanding in share-based payment arrangement at end of period (in euros per share) | $ / shares   $ 22.66   $ 23.04