v3.25.2
GOODWILL AND INTANGIBLE ASSETS (Details 1) - USD ($)
$ in Millions
6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2021
Dec. 31, 2024
Dec. 31, 2023
Goodwill [Line Items]          
Goodwill $ 1,425.5 $ 1,423.4   $ 1,423.6 $ 1,424.0
Goodwill, Period Increase (Decrease) 2.0 (0.3)      
Goodwill, Foreign Currency Translation Gain (Loss) (0.1) (0.3)      
Chlor Alkali Products and Vinyls          
Goodwill [Line Items]          
Goodwill 1,276.3 1,275.9   1,276.4 1,276.1
Goodwill, Period Increase (Decrease) 0.0 0.0      
Goodwill, Foreign Currency Translation Gain (Loss) (0.1) (0.2)      
Goodwill, Impairment Loss     $ 557.6    
Epoxy          
Goodwill [Line Items]          
Goodwill 144.8 145.1   144.8 145.2
Goodwill, Period Increase (Decrease) 0.0 0.0      
Goodwill, Foreign Currency Translation Gain (Loss) 0.0 (0.1)      
Goodwill, Impairment Loss     $ 142.2    
Winchester          
Goodwill [Line Items]          
Goodwill 4.4 2.4   $ 2.4 $ 2.7
Goodwill, Period Increase (Decrease) 2.0 (0.3)      
Goodwill, Foreign Currency Translation Gain (Loss) $ 0.0 $ 0.0