Consolidated Statements of Earnings and Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Income Statement [Abstract]
OCI Pension and postretirement activity, net of tax	$ (0.2)	$ (0.1)	$ (0.5)	$ (0.4)
OCI gain (loss) on cash flow hedge, tax	$ 0.6	$ (1.6)	$ 1.7	$ (0.6)

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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