Business Segment Information - Schedule of Identifiable Assets by Business Segments and by Geographical Segments (Details) - USD ($) $ in Millions		Mar. 31, 2021	Sep. 30, 2020
Assets
Assets		$ 6,343.8	$ 5,815.9
Operating Segments | Access Equipment
Assets
Assets		2,812.8	2,893.8
Operating Segments | Access Equipment | United States
Assets
Assets		1,991.7	2,151.4
Operating Segments | Access Equipment | Europe, Africa and Middle East
Assets
Assets		445.8	383.4
Operating Segments | Access Equipment | Rest of the World
Assets
Assets		375.3	359.0
Operating Segments | Defense
Assets
Assets	[1]	1,233.5	1,085.9
Operating Segments | Defense | United States
Assets
Assets	[1]	1,228.7	1,078.7
Operating Segments | Defense | Rest of the World
Assets
Assets	[1]	4.8	7.2
Operating Segments | Fire & Emergency | United States
Assets
Assets	[1]	510.5	563.6
Operating Segments | Commercial
Assets
Assets		431.7	418.2
Operating Segments | Commercial | United States
Assets
Assets		369.7	370.7
Operating Segments | Commercial | Rest of the World
Assets
Assets		62.0	47.5
Corporate, Non-segment | United States
Assets
Assets	[2]	$ 1,355.3	$ 854.4

[1] Results have been reclassified to reflect the move of the airport snow removal vehicle business from the Fire & Emergency segment to the Defense segment.

[2] Primarily includes cash and short-term investments and the Company’s global headquarters.