Business Segment Information (Details 3) - USD ($) $ in Millions		3 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2016
Revenue and assets by geography
Identifiable assets		$ 4,491.0		$ 4,513.8
Net sales		1,211.4	$ 1,252.0
United States
Revenue and assets by geography
Net sales		1,018.3	904.4
Other North America
Revenue and assets by geography
Net sales		35.7	61.5
Europe, Africa and Middle East
Revenue and assets by geography
Net sales		71.6	200.1
Rest of the World
Revenue and assets by geography
Net sales		85.8	86.0
Access Equipment
Revenue and assets by geography
Net sales		489.2	529.8
Defense
Revenue and assets by geography
Net sales		294.2	316.9
Fire & Emergency
Revenue and assets by geography
Net sales		229.1	205.4
Commercial
Revenue and assets by geography
Net sales		198.1	199.9
Operating Segments
Revenue and assets by geography
Net sales		1,211.4	1,252.0
Operating Segments | Access Equipment
Revenue and assets by geography
Identifiable assets		2,463.3		2,571.2
Net sales		489.2	529.8
Operating Segments | Access Equipment | United States
Revenue and assets by geography
Identifiable assets		1,783.6		1,856.0
Operating Segments | Access Equipment | Europe
Revenue and assets by geography
Identifiable assets	[1]	483.7		521.5
Operating Segments | Access Equipment | Rest of the World
Revenue and assets by geography
Identifiable assets		196.0		193.7
Operating Segments | Defense
Revenue and assets by geography
Identifiable assets		571.1		525.2
Net sales		294.5	318.0
Operating Segments | Defense | United States
Revenue and assets by geography
Identifiable assets		568.5		522.2
Operating Segments | Defense | Rest of the World
Revenue and assets by geography
Identifiable assets		2.6		3.0
Operating Segments | Fire & Emergency
Revenue and assets by geography
Net sales		232.5	207.5
Operating Segments | Fire & Emergency | United States
Revenue and assets by geography
Identifiable assets		518.5		522.7
Operating Segments | Commercial
Revenue and assets by geography
Identifiable assets		386.4		391.8
Net sales		199.2	$ 200.3
Operating Segments | Commercial | United States
Revenue and assets by geography
Identifiable assets		355.1		358.4
Operating Segments | Commercial | Rest of the World
Revenue and assets by geography
Identifiable assets	[1]	31.3		33.4
Corporate, non-segment
Revenue and assets by geography
Identifiable assets		551.7		502.9
Corporate, non-segment | United States
Revenue and assets by geography
Identifiable assets	[2]	457.1		408.3
Corporate, non-segment | Rest of the World
Revenue and assets by geography
Identifiable assets	[3]	$ 94.6		$ 94.6

[1] Includes investments in unconsolidated affiliates.

[2] Primarily includes cash and short-term investments.

[3] Includes a corporate-led manufacturing facility that supports multiple operating segments.