Condensed Consolidated Statements of Earnings and Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Income Statement [Abstract]
Pension and postretirement activity, tax	$ 0.1	$ (0.1)	$ 0.4	$ (0.9)
Deferred gain on hedging activity, tax	$ (1.6)	$ 0.3	$ (0.6)	$ 0.0
Diluted net earnings per share	$ 0.62	$ 0.98	$ 1.17	$ 1.79