Condensed Consolidated Statements of Earnings and Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Income Statement [Abstract]
Pension and postretirement activity, tax	$ (0.6)	$ 0.4	$ 0.9	$ 0.7
Deferred gain on hedging activity, tax	$ 0.9	$ 1.4	$ (2.8)	$ 2.0
Diluted net earnings per share	$ 1.01	$ 0.57	$ 1.61	$ 1.20