Freeport, TX chlor alkali production capacity reduction announced on December 11, 2019.

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Reduction of diaphragm-grade chlor alkali capacity at our McIntosh, AL facility announced in 2021.

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Total chlor alkali product segment production capacity decrease announced on March 21, 2016

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RESTRUCTURING CHARGES (Details 1) $ in Millions	3 Months Ended				6 Months Ended		28 Months Ended	29 Months Ended	43 Months Ended	87 Months Ended
RESTRUCTURING CHARGES (Details 1) $ in Millions	Jun. 30, 2023 USD ($)	Mar. 31, 2023 USD ($)	Jun. 30, 2022 USD ($)	Mar. 31, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Oct. 21, 2021 T	Dec. 11, 2019 T	Mar. 21, 2016 T
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 19.2	$ 60.9	$ 3.6	$ 3.1	$ 80.1	$ 6.7				$ 376.7
Inception to date Amounts Utilized (cash)										169.0
Inception to date Amounts Utilized (non-cash)										158.0
Epoxy Optimization Plan \| Epoxy
Restructuring Cost and Reserve [Line Items]
Restructuring charges	13.3				71.1					79.1
Additional restructuring and related expected cost	50.0				50.0		$ 50.0	$ 50.0	$ 50.0	50.0
McIntosh Plan \| Chlor Alkali Products and Vinyls
Restructuring Cost and Reserve [Line Items]
Restructuring charges	2.5		0.7		3.9	1.6	17.8
Additional restructuring and related expected cost	30.0				30.0		30.0	30.0	30.0	30.0
McIntosh Restructuring Capacity Reduction \| T											400,000
Freeport 2021 Plan \| Chlor Alkali Products and Vinyls
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1.4		1.2		2.1	1.5		11.2
Additional restructuring and related expected cost	15.0				15.0		15.0	15.0	15.0	15.0
Freeport 2019 Plan \| Chlor Alkali Products and Vinyls
Restructuring Cost and Reserve [Line Items]
Restructuring charges	2.0		1.5		3.0	3.2			75.6
Additional restructuring and related expected cost	30.0				30.0		30.0	30.0	30.0	30.0
Freeport Chlor Alkali Capacity Reduction \| T												230,000
Chlor Alkali 2016 Plan \| Chlor Alkali Products and Vinyls
Restructuring Cost and Reserve [Line Items]
Restructuring charges			$ 0.2			$ 0.4				182.7
Additional restructuring and related expected cost	$ 0.0				$ 0.0		$ 0.0	$ 0.0	$ 0.0	$ 0.0
Total Product Segment Production Capacity Decrease \| T													433,000