v3.26.1
EARNINGS PER SHARE (Details) - USD ($)
$ / shares in Units, $ in Millions
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Numerator:    
Net income attributable to equity holders of Constellium $ 199 $ 37
Denominator:    
Basic - weighted-average ordinary shares outstanding (in shares) 135,394,675 142,495,499
Dilutive effect of non-vested restricted stock units and performance-based restricted stock units (in shares) 4,689,980 1,594,032
Diluted - weighted-average ordinary shares, of restricted stock units and performance-based restricted stock units (in shares) 140,084,655 144,089,531
Basic earnings per share (in USD per share) $ 1.47 $ 0.26
Diluted earnings per share (in USD per share) $ 1.42 $ 0.26
Antidilutive securities excluded from computation of earnings per share (in shares) 0 0