v3.26.1
EARNINGS PER SHARE - Earnings Per Share Computation (Details) - USD ($)
$ / shares in Units, shares in Millions, $ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Earnings Per Share [Abstract]        
Loss from continuing operations $ (132) $ (473) $ (358) $ (959)
Net income attributable to noncontrolling interests (11) (13) (19) (25)
Loss from continuing operations (143) (486) (377) (984)
Loss from discontinued operations, net of tax (2) 0 (5) 0
Net loss $ (145) $ (486) $ (382) $ (984)
Weighted average number of shares:        
Basic (in shares) 571 495 571 495
Employee stock plans (in shares) 0 0 0 0
Diluted (in shares) 571 495 571 495
Earnings Per Share, Basic [Abstract]        
Continuing operations $ (0.25) $ (0.98) $ (0.66) $ (1.99)
Discontinued operations 0 0 (0.01) 0
Earnings Per Share, Basic, Total (0.25) (0.98) (0.67) (1.99)
Loss per common share attributable to Cliffs shareholders - diluted        
Continuing operations (0.25) (0.98) (0.66) (1.99)
Discontinued operations 0 0 (0.01) 0
Earnings Per Share, Diluted, Total $ (0.25) $ (0.98) $ (0.67) $ (1.99)