Guarantees (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance at beginning of period	$ 27.4	$ 28.8	$ 27.5	$ 32.1
Provision for warranties during the period	4.0	3.5	10.3	11.3
Standard Product Warranty Accrual, Additions from Business Acquisition	0.0	0.0	1.9	0.0
Warranty claims during the period	(4.5)	(5.3)	(12.8)	(16.4)
Balance at end of period	$ 26.9	$ 27.0	$ 26.9	$ 27.0