Consolidated Comprehensive Income Statements (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Statement of Comprehensive Income [Abstract]
Tax effect on translation adjustments	$ (1.2)	$ 46.2
Tax effect on net gain (loss) on derivatives	0.9	(22.0)
Tax effect on derivatives reclassification adjustments	4.8	27.8
Tax effect on pension and postretirement benefits reclassification adjustments	$ 3.4	$ 3.3

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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