Condensed Consolidated Statements of Comprehensive Income - USD ($) shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Net Income (Loss) Attributable to Parent [Abstract]
Net revenues	$ 503.8	$ 403.2	$ 965.6	$ 817.5
Cost of sales	316.8	252.7	606.1	514.1
Gross profit	187.0	150.5	359.5	303.4
Selling, general and administrative expenses	98.7	83.6	205.5	164.0
Net legacy and separation-related expenses	0.9	0.8	6.1	1.2
Other loss (income), net	1.4	(0.8)	43.6	(72.5)
Operating income	86.0	66.9	104.3	210.7
Net pension and other postretirement plan income	(1.2)	(0.9)	(2.4)	(1.8)
Net interest and other financing expenses	27.7	16.9	53.2	34.4
Income before income taxes	59.5	50.9	53.5	178.1
Income tax expense	14.2	12.6	40.4	45.9
Income from continuing operations	45.3	38.3	13.1	132.2
Loss from discontinued operations, net of tax	(0.5)	(0.7)	(1.1)	(3.0)
Net income	$ 44.8	$ 37.6	$ 12.0	$ 129.2
NET EARNINGS PER SHARE
Continuing operations, basic earnings (loss) per share (usd per share)	$ 0.35	$ 0.30	$ 0.10	$ 1.03
Discontinued operations, basic earnings (loss) per share (usd per share)	0	(0.01)	(0.01)	(0.02)
Basic (loss) earnings per share (usd per share)	0.35	0.29	0.09	1.01
Continuing operations, diluted earnings (loss) per share (usd per share)	0.35	0.30	0.10	1.02
Discontinued operations, diluted earnings (loss) per share (usd per share)	0	(0.01)	(0.01)	(0.02)
Diluted earnings per share (usd per share)	$ 0.35	$ 0.29	$ 0.09	$ 1.00
Weighted average common shares outstanding
Basic (in shares)	127.8	127.6	127.7	128.2
Diluted (in shares)	128.4	128.2	128.3	128.9
COMPREHENSIVE INCOME
Net income	$ 44.8	$ 37.6	$ 12.0	$ 129.2
Other comprehensive loss, net of tax
Currency translation adjustments	(1.7)	(0.1)	0.0	(6.6)
Amortization of pension and other postretirement plan prior service credits	(0.4)	(0.4)	(0.8)	(0.8)
Other comprehensive loss	(2.1)	(0.5)	(0.8)	(7.4)
Comprehensive income	$ 42.7	$ 37.1	$ 11.2	$ 121.8

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
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-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
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-Section S99
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
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