Consolidated Statement of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Other comprehensive income (loss)
Pension and other postretirement (benefit) expense tax	$ 7.4	$ (15.4)	$ (76.0)
Net change in cash flow hedges, tax benefit (expense)	$ 11.2	$ 5.3	$ (14.3)

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

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