v3.26.1
Earnings (loss) per share - Summary of basic and diluted earnings (loss) per share (Detail) - USD ($)
$ / shares in Units, $ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Numerator:        
Net income (loss) $ (16.9) $ 62.4 $ (25.9) $ 97.4
Net loss attributable to noncontrolling interests (1.6) (0.1) (3.4) (0.1)
Net income (loss) attributable to INNIO N.V. shareholders $ (15.3) $ 62.5 $ (22.5) $ 97.5
Weighted-average shares outstanding:        
Weighted average number of shares outstanding, basic 750,000,000 750,000,000 750,000,000 750,000,000
Effect of potentially dilutive RSUs 0 0 0 0
Weighted average number of shares outstanding, diluted 750,000,000 750,000,000 750,000,000 750,000,000
Net earnings (loss) per share:        
Earnings per share, basic $ (0.02) $ 0.08 $ (0.03) $ 0.13
Earnings per share, diluted $ (0.02) $ 0.08 $ (0.03) $ 0.13