SEGMENT INFORMATION (Details 3) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Disaggregation of Revenue [Line Items]
Sales	$ 1,635.3	$ 1,844.3
Transferred over Time
Disaggregation of Revenue [Line Items]
Sales	19.8	22.7
Chlor Alkali Products and Vinyls
Disaggregation of Revenue [Line Items]
Sales	884.6	1,117.1
Chlor Alkali Products and Vinyls | Caustic soda
Disaggregation of Revenue [Line Items]
Sales	355.7	546.8
Chlor Alkali Products and Vinyls | Chlorine, chlorine-derivatives and other co-products
Disaggregation of Revenue [Line Items]
Sales	528.9	570.3
Epoxy
Disaggregation of Revenue [Line Items]
Sales	341.3	360.7
Epoxy | Aromatics and allylics
Disaggregation of Revenue [Line Items]
Sales	154.9	142.3
Epoxy | Epoxy resins
Disaggregation of Revenue [Line Items]
Sales	186.4	218.4
Winchester
Disaggregation of Revenue [Line Items]
Sales	409.4	366.5
Winchester | Commercial
Disaggregation of Revenue [Line Items]
Sales	242.8	200.5
Winchester | Military and law enforcement
Disaggregation of Revenue [Line Items]
Sales	$ 166.6	$ 166.0