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RESTRUCTURING ACTIVITIES - Asset Optimization and Corporate Restructuring (Details) - 2023 Asset Optimization and Corporate Restructuring - USD ($) $ in Millions	3 Months Ended		6 Months Ended		34 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026
RESTRUCTURING ACTIVITIES
Net pre-tax restructuring charges	$ 1.3	$ 4.1	$ 2.8	$ 6.5	$ 87.4
Activities
Reserve balance at December 31, 2025			1.1
Restructuring charges			2.8
Payments			(2.9)
Reserve balance at June 30, 2026	1.0		1.0		1.0
Severance and related benefit credits (credits)
RESTRUCTURING ACTIVITIES
Net pre-tax restructuring charges		0.6		1.0	17.4
Activities
Reserve balance at December 31, 2025			1.1
Payments			(0.1)
Reserve balance at June 30, 2026	1.0		1.0		1.0
Asset Related Charges
RESTRUCTURING ACTIVITIES
Net pre-tax restructuring charges	1.3	3.5	2.8	5.5	60.8
Restructuring costs expected to incur	0.7		0.7		0.7
Activities
Restructuring charges			2.8
Payments			(2.8)
Accelerated depreciation charges of plant, property and equipment associated with the exit
RESTRUCTURING ACTIVITIES
Net pre-tax restructuring charges					32.6
Decommissioning and other charges
RESTRUCTURING ACTIVITIES
Net pre-tax restructuring charges					28.2
Contract terminations
RESTRUCTURING ACTIVITIES
Net pre-tax restructuring charges					$ 9.2
Corporate
RESTRUCTURING ACTIVITIES
Net pre-tax restructuring charges				(0.1)
Engineered Materials
RESTRUCTURING ACTIVITIES
Net pre-tax restructuring charges				0.1
Polymer Solutions
RESTRUCTURING ACTIVITIES
Net pre-tax restructuring charges	$ 1.3	$ 4.1	$ 2.8	$ 6.5