Business Segment Information - Schedule of Income (Loss) from Continuing operations by Product Lines and Reportable Segments (Details) - USD ($) $ in Millions		3 Months Ended
		Dec. 31, 2021	Dec. 31, 2020
Operating income (loss):
Operating income (loss)		$ 18.0	$ 95.9
Interest expense, net of interest income		(11.8)	(11.4)
Miscellaneous other income (expense)		(5.6)	(1.5)
Income before income taxes and earnings (losses) of unconsolidated affiliates		0.6	83.0
Operating Segments | Access Equipment
Operating income (loss):
Operating income (loss)	[1]	32.3	24.9
Operating Segments | Defense
Operating income (loss):
Operating income (loss)		10.6	52.8
Operating Segments | Fire & Emergency
Operating income (loss):
Operating income (loss)		9.3	35.1
Operating Segments | Commercial
Operating income (loss):
Operating income (loss)		(3.3)	11.9
Corporate, Non-segment
Operating income (loss):
Operating income (loss)		$ (30.9)	$ (28.8)

[1] Results for the three months ended December 31, 2020 include a $4.8 million charge for restructuring costs and $3.2 million of other costs related to restructuring plans.