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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Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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RESTRUCTURING CHARGES (Details 1) $ in Millions	3 Months Ended						9 Months Ended		52 Months Ended	111 Months Ended
RESTRUCTURING CHARGES (Details 1) $ in Millions	Sep. 30, 2025 USD ($)	Jun. 30, 2025 USD ($)	Mar. 31, 2025 USD ($)	Sep. 30, 2024 USD ($)	Jun. 30, 2024 USD ($)	Mar. 31, 2024 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2025 USD ($)	Oct. 21, 2021 T	Dec. 11, 2019 T
Restructuring Cost and Reserve [Line Items]
McIntosh Restructuring Capacity Reduction \| T											400,000
Freeport Chlor Alkali Capacity Reduction \| T												230,000
Restructuring charges	$ 2.9	$ 7.4	$ 4.0	$ 7.9	$ 6.8	$ 8.3	$ 14.3	$ 23.0	$ 240.7
Additional restructuring and related expected cost	75.0						75.0
Inception to date Amounts Utilized (cash)										$ 152.2
Inception to date Amounts Utilized (non-cash)										$ 79.9
Epoxy
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0.0			0.0			0.0	0.0	111.8
Chlor Alkali Products and Vinyls
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 0.0			$ 0.0			$ 0.0	$ 0.0	$ 128.9