v3.25.2
SEGMENT INFORMATION (Details 1) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended 52 Months Ended
Jun. 30, 2025
Mar. 31, 2025
Jun. 30, 2024
Mar. 31, 2024
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Dec. 31, 2024
Gross Margin [Abstract]                
Sales $ 1,758.3   $ 1,644.0   $ 3,402.5 $ 3,279.3    
Cost of goods sold 1,620.2   1,406.2   3,115.7 2,834.2    
Gross Profit 138.1   237.8   286.8 445.1    
Income (Loss) before Income Taxes [Abstract]                
Segment Reporting, Other Segment Item, Amount (96.6)   (94.6)   (197.6) (196.5)    
Restructuring charges (7.4) $ (4.0) (6.8) $ (8.3) (11.4) (15.1) $ (237.8)  
Other Operating Income 0.2       0.2 0.2    
Interest Expense, Operating and Nonoperating (46.8)   (46.6)   (95.3) (91.2)    
Interest income 1.2   0.9   2.4 1.7    
Non-operating pension income 4.9   5.9   10.6 12.7    
Income (loss) before taxes (6.8)   96.6   (4.7) 156.9    
Depreciation and amortization expense                
Depreciation and amortization 129.9   129.0   262.1 258.7    
Assets                
Assets 7,667.9   7,660.6   7,667.9 7,660.6 7,667.9 $ 7,579.1
United States                
Gross Margin [Abstract]                
Sales 1,201.9   1,189.5   2,339.1 2,378.4    
Europe                
Gross Margin [Abstract]                
Sales 155.8   154.5   303.4 292.5    
Other foreign                
Gross Margin [Abstract]                
Sales 400.6   300.0   760.0 608.4    
Chlor Alkali Products and Vinyls                
Gross Margin [Abstract]                
Sales 979.5   920.3   1,904.0 1,804.9    
Cost of goods sold 871.8   778.5   1,673.8 1,544.5    
Gross Profit 107.7   141.8   230.2 260.4    
Income (Loss) before Income Taxes [Abstract]                
Segment Reporting, Other Segment Item, Amount (42.8)   (42.5)   (87.0) (84.5)    
Restructuring charges 0.0   0.0   0.0 0.0 (127.0)  
Other Operating Income 0.0       0.0 0.0    
Interest Expense, Operating and Nonoperating 0.0   0.0   0.0 0.0    
Interest income 0.0   0.0   0.0 0.0    
Non-operating pension income 0.0   0.0   0.0 0.0    
Income (loss) before taxes 64.9   99.3   143.2 175.9    
Depreciation and amortization expense                
Depreciation and amortization 106.3   105.9   213.5 212.6    
Assets                
Assets 5,277.4   5,428.1   5,277.4 5,428.1 5,277.4  
Chlor Alkali Products and Vinyls | United States                
Gross Margin [Abstract]                
Sales 664.2   671.5   1,311.1 1,307.1    
Chlor Alkali Products and Vinyls | Europe                
Gross Margin [Abstract]                
Sales 42.0   45.0   75.2 80.8    
Chlor Alkali Products and Vinyls | Other foreign                
Gross Margin [Abstract]                
Sales 273.3   203.8   517.7 417.0    
Epoxy                
Gross Margin [Abstract]                
Sales 331.2   317.7   662.9 659.0    
Cost of goods sold 340.0   307.6   685.1 646.7    
Gross Profit (8.8)   10.1   (22.2) 12.3    
Income (Loss) before Income Taxes [Abstract]                
Segment Reporting, Other Segment Item, Amount (14.9)   (13.1)   (29.9) (27.1)    
Restructuring charges 0.0   0.0   0.0 0.0 (110.8)  
Other Operating Income 0.0       0.0 0.0    
Interest Expense, Operating and Nonoperating 0.0   0.0   0.0 0.0    
Interest income 0.0   0.0   0.0 0.0    
Non-operating pension income 0.0   0.0   0.0 0.0    
Income (loss) before taxes (23.7)   (3.0)   (52.1) (14.8)    
Depreciation and amortization expense                
Depreciation and amortization 13.1   13.4   25.9 26.9    
Assets                
Assets 949.3   992.4   949.3 992.4 949.3  
Epoxy | United States                
Gross Margin [Abstract]                
Sales 140.8   166.8   284.9 338.1    
Epoxy | Europe                
Gross Margin [Abstract]                
Sales 93.4   74.9   195.2 164.2    
Epoxy | Other foreign                
Gross Margin [Abstract]                
Sales 97.0   76.0   182.8 156.7    
Winchester                
Gross Margin [Abstract]                
Sales 447.6   406.0   835.6 815.4    
Cost of goods sold 402.6   312.8   745.2 629.1    
Gross Profit 45.0   93.2   90.4 186.3    
Income (Loss) before Income Taxes [Abstract]                
Segment Reporting, Other Segment Item, Amount (20.0)   (22.9)   (42.6) (43.8)    
Restructuring charges 0.0   0.0   0.0 0.0    
Other Operating Income 0.0       0.0 0.0    
Interest Expense, Operating and Nonoperating 0.0   0.0   0.0 0.0    
Interest income 0.0   0.0   0.0 0.0    
Non-operating pension income 0.0   0.0   0.0 0.0    
Income (loss) before taxes 25.0   70.3   47.8 142.5    
Depreciation and amortization expense                
Depreciation and amortization 7.9   8.2   17.4 16.2    
Assets                
Assets 866.7   765.1   866.7 765.1 866.7  
Winchester | United States                
Gross Margin [Abstract]                
Sales 396.9   351.2   743.1 733.2    
Winchester | Europe                
Gross Margin [Abstract]                
Sales 20.4   34.6   33.0 47.5    
Winchester | Other foreign                
Gross Margin [Abstract]                
Sales 30.3   20.2   59.5 34.7    
Corporate/ other                
Gross Margin [Abstract]                
Sales 0.0   0.0   0.0 0.0    
Cost of goods sold 5.8   7.3   11.6 13.9    
Gross Profit (5.8)   (7.3)   (11.6) (13.9)    
Income (Loss) before Income Taxes [Abstract]                
Segment Reporting, Other Segment Item, Amount (18.9)   (16.1)   (38.1) (41.1)    
Restructuring charges (7.4)   (6.8)   (11.4) (15.1)    
Other Operating Income (0.2)       (0.2) 0.2    
Interest Expense, Operating and Nonoperating 46.8   46.6   95.3 91.2    
Interest income 1.2   0.9   2.4 1.7    
Non-operating pension income 4.9   5.9   10.6 12.7    
Income (loss) before taxes (73.0)   (70.0)   (143.6) (146.7)    
Depreciation and amortization expense                
Depreciation and amortization 2.6   1.5   5.3 3.0    
Assets                
Assets 574.5   475.0   574.5 475.0 $ 574.5  
Corporate/ other | United States                
Gross Margin [Abstract]                
Sales 0.0   0.0   0.0 0.0    
Corporate/ other | Europe                
Gross Margin [Abstract]                
Sales 0.0   0.0   0.0 0.0    
Corporate/ other | Other foreign                
Gross Margin [Abstract]                
Sales $ 0.0   $ 0.0   $ 0.0 $ 0.0