Condensed Consolidated Statements of Earnings and Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Statement [Abstract]
Pension and postretirement activity, tax	$ (0.1)	$ (0.6)	$ (0.9)	$ 0.9
Deferred gain on hedging activity, tax	$ 0.3	$ 0.9	$ 0.0	$ (2.8)
Diluted net earnings per share	$ 0.98	$ 1.02	$ 1.79	$ 1.63