v3.26.1
SPECIAL (GAINS) AND CHARGES - Restructuring Activity Related to the One Ecolab Initiative (Details) - One Ecolab Initiative Program - USD ($)
$ in Millions
 6 Months Ended 12 Months Ended
Jun. 30, 2026
Dec. 31, 2025
Restructuring Cost and Reserve [Line Items]    
Recorded expense and accrual $ 51.4 $ 193.5
Net cash payments (64.1) (102.7)
Reclassification   5.3
Restructuring liability, at end of period 83.4 96.1
Employee Severance    
Restructuring Cost and Reserve [Line Items]    
Recorded expense and accrual 40.4 148.2
Net cash payments (57.0) (55.7)
Restructuring liability, at end of period 75.9 92.5
Other    
Restructuring Cost and Reserve [Line Items]    
Recorded expense and accrual 11.0 45.3
Net cash payments (7.1) (47.0)
Reclassification   5.3
Restructuring liability, at end of period $ 7.5 $ 3.6