Goodwill and Purchased Intangible Assets (Details) $ in Millions	3 Months Ended
	Dec. 31, 2016 USD ($)
Changes in goodwill
Net goodwill at the beginning of the period	$ 1,003.5
Foreign currency translation	(12.5)
Net goodwill at the end of the period	991.0
Access Equipment
Changes in goodwill
Net goodwill at the beginning of the period	876.6
Foreign currency translation	(12.5)
Net goodwill at the end of the period	864.1
Fire & Emergency
Changes in goodwill
Net goodwill at the beginning of the period	106.1
Foreign currency translation	0.0
Net goodwill at the end of the period	106.1
Commercial
Changes in goodwill
Net goodwill at the beginning of the period	20.8
Foreign currency translation	0.0
Net goodwill at the end of the period	$ 20.8