SEGMENT INFORMATION (Details 2) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Disaggregation of Revenue [Line Items]
Sales	$ 1,635.3	$ 1,844.3
United States
Disaggregation of Revenue [Line Items]
Sales	1,189.0	1,248.0
Europe
Disaggregation of Revenue [Line Items]
Sales	132.0	176.9
Other foreign
Disaggregation of Revenue [Line Items]
Sales	314.3	419.4
Chlor Alkali Products and Vinyls
Disaggregation of Revenue [Line Items]
Sales	884.6	1,117.1
Chlor Alkali Products and Vinyls | United States
Disaggregation of Revenue [Line Items]
Sales	635.6	766.5
Chlor Alkali Products and Vinyls | Europe
Disaggregation of Revenue [Line Items]
Sales	35.8	72.4
Chlor Alkali Products and Vinyls | Other foreign
Disaggregation of Revenue [Line Items]
Sales	213.2	278.2
Epoxy
Disaggregation of Revenue [Line Items]
Sales	341.3	360.7
Epoxy | United States
Disaggregation of Revenue [Line Items]
Sales	171.3	151.6
Epoxy | Europe
Disaggregation of Revenue [Line Items]
Sales	89.3	96.6
Epoxy | Other foreign
Disaggregation of Revenue [Line Items]
Sales	80.7	112.5
Winchester
Disaggregation of Revenue [Line Items]
Sales	409.4	366.5
Winchester | United States
Disaggregation of Revenue [Line Items]
Sales	382.1	329.9
Winchester | Europe
Disaggregation of Revenue [Line Items]
Sales	6.9	7.9
Winchester | Other foreign
Disaggregation of Revenue [Line Items]
Sales	$ 20.4	$ 28.7