BUSINESS SEGMENT INFORMATION - Reportable Segment Information by Geographic Area (Details) - USD ($) $ in Millions	2 Months Ended	3 Months Ended							10 Months Ended	11 Months Ended	12 Months Ended
	Sep. 30, 2025	Jul. 31, 2025	Apr. 30, 2025	Jan. 31, 2025	Oct. 31, 2024	Jul. 31, 2024	Apr. 30, 2024	Jan. 31, 2024	Sep. 30, 2024	Sep. 30, 2025	Oct. 31, 2024	Oct. 31, 2023
Segment Reporting Information [Line Items]
Net sales	$ 701.3	$ 1,134.7	$ 1,101.3	$ 995.8	$ 1,107.0	$ 1,164.9	$ 1,117.5	$ 965.5	$ 3,972.8	$ 3,933.1	$ 4,354.9	$ 4,175.3
Costs of products sold	541.7	877.4	841.4	801.1	879.1	920.0	874.9	781.8	3,155.0	3,061.6	3,455.8	3,246.7
Selling, general and administrative expenses	126.0	157.0	161.8	157.1	146.3	152.8	155.9	134.9	535.5	601.9	589.9	510.3
Acquisition and integration related costs	1.7	1.2	2.0	2.2	2.4	2.0	11.5	2.6	17.4	7.1	18.5	19.0
Restructuring and other charges	20.1	25.2	14.6	2.7	3.8	2.7	(6.8)	5.7	2.7	62.6	5.4	18.7
Non-cash asset impairment charges	10.1	3.4	10.7	13.7	0.7	0.2	0.4	1.3	2.3	37.9	2.6	20.3
Gain on disposal of properties, plants and equipment, net									(7.1)	(7.5)	(9.1)	(2.5)
Loss (gain) on disposal of businesses, net	0.5	0.0	0.5	0.9	0.1	(46.1)	0.0	0.0	(46.1)	1.9	(46.0)	(64.0)
Operating profit	$ 5.0	$ 73.1	$ 69.8	$ 19.7	$ 77.3	$ 136.7	$ 81.9	$ 41.9	$ 313.1	167.6	337.8	426.8
Customized Polymer Solutions
Segment Reporting Information [Line Items]
Net sales										1,169.6	1,135.1	917.1
Costs of products sold										915.9	912.4	706.3
Selling, general and administrative expenses										207.2	164.0	110.8
Acquisition and integration related costs										7.1	17.2	10.8
Restructuring and other charges										9.6	2.3	2.1
Non-cash asset impairment charges										3.1	0.3	0.1
Gain on disposal of properties, plants and equipment, net										(0.2)	(0.2)	0.2
Loss (gain) on disposal of businesses, net										0.0	0.0	(9.4)
Operating profit										26.9	39.1	96.2
Durable Metal Solutions
Segment Reporting Information [Line Items]
Net sales										1,368.2	1,602.1	1,631.7
Costs of products sold										1,085.7	1,282.9	1,323.1
Selling, general and administrative expenses										167.3	183.7	166.5
Acquisition and integration related costs										0.0	0.0	0.0
Restructuring and other charges										12.5	3.0	1.7
Non-cash asset impairment charges										2.3	0.4	1.8
Gain on disposal of properties, plants and equipment, net										(7.6)	(2.8)	(4.5)
Loss (gain) on disposal of businesses, net										0.0	0.0	0.0
Operating profit										108.0	134.9	143.1
Sustainable Fiber Solutions
Segment Reporting Information [Line Items]
Net sales										1,096.9	1,242.3	1,307.9
Costs of products sold										846.9	994.3	988.4
Selling, general and administrative expenses										154.0	161.7	167.5
Acquisition and integration related costs										0.0	1.3	8.2
Restructuring and other charges										36.4	(0.8)	12.5
Non-cash asset impairment charges										31.8	1.7	17.7
Gain on disposal of properties, plants and equipment, net										0.3	(3.4)	2.1
Loss (gain) on disposal of businesses, net										0.5	0.0	(54.6)
Operating profit										27.0	87.5	166.1
Integrated Solutions
Segment Reporting Information [Line Items]
Net sales										298.4	375.4	318.6
Costs of products sold										213.1	266.2	228.9
Selling, general and administrative expenses										73.4	80.5	65.5
Acquisition and integration related costs										0.0	0.0	0.0
Restructuring and other charges										4.1	0.9	2.4
Non-cash asset impairment charges										0.7	0.2	0.7
Gain on disposal of properties, plants and equipment, net										0.0	(2.7)	(0.3)
Loss (gain) on disposal of businesses, net										1.4	(46.0)	0.0
Operating profit										5.7	76.3	21.4
United States
Segment Reporting Information [Line Items]
Net sales										2,025.9	2,312.5	2,289.0
United States | Customized Polymer Solutions
Segment Reporting Information [Line Items]
Net sales										496.3	508.8	442.3
United States | Durable Metal Solutions
Segment Reporting Information [Line Items]
Net sales										251.8	314.7	336.4
United States | Sustainable Fiber Solutions
Segment Reporting Information [Line Items]
Net sales										1,051.9	1,188.4	1,254.4
United States | Integrated Solutions
Segment Reporting Information [Line Items]
Net sales										225.9	300.6	255.9
Europe, Middle East and Africa
Segment Reporting Information [Line Items]
Net sales										1,309.7	1,388.0	1,310.9
Europe, Middle East and Africa | Customized Polymer Solutions
Segment Reporting Information [Line Items]
Net sales										467.4	438.2	380.1
Europe, Middle East and Africa | Durable Metal Solutions
Segment Reporting Information [Line Items]
Net sales										798.8	905.1	893.4
Europe, Middle East and Africa | Sustainable Fiber Solutions
Segment Reporting Information [Line Items]
Net sales										0.9	0.7	0.6
Europe, Middle East and Africa | Integrated Solutions
Segment Reporting Information [Line Items]
Net sales										42.6	44.0	36.8
Asia Pacific and Other Americas
Segment Reporting Information [Line Items]
Net sales										597.5	654.4	575.4
Asia Pacific and Other Americas | Customized Polymer Solutions
Segment Reporting Information [Line Items]
Net sales										205.9	188.1	94.7
Asia Pacific and Other Americas | Durable Metal Solutions
Segment Reporting Information [Line Items]
Net sales										317.6	382.3	401.9
Asia Pacific and Other Americas | Sustainable Fiber Solutions
Segment Reporting Information [Line Items]
Net sales										44.1	53.2	52.9
Asia Pacific and Other Americas | Integrated Solutions
Segment Reporting Information [Line Items]
Net sales										$ 29.9	$ 30.8	$ 25.9