Consolidated Comprehensive Income Statements (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Statement of Comprehensive Income [Abstract]
Translation adjustments, tax	$ 4.0	$ (81.0)	$ 18.4	$ (69.1)
Net gain on derivatives, tax	6.3	17.1	5.1	(1.0)
Derivatives, tax	(0.8)	(15.6)	9.2	9.9
Pension and postretirement benefits, net	$ 2.8	$ 3.4	$ 9.7	$ 10.3

Amount of tax expense (benefit), before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount, before reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount of tax (expense) benefit for reclassification adjustment from accumulated other comprehensive (income) loss of defined benefit plan.

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