Business Separation, Restructuring, and Cost Reduction Actions (Details) $ in Millions	9 Months Ended
	Jun. 30, 2017 USD ($)
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	$ 0.6
Current Period Charge	0.5
Cash Payments	(1.1)
Restructuring reserve, ending balance	0.0
Severance and Other Benefits
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	0.6
Current Period Charge	0.5
Cash Payments	(1.1)
Restructuring reserve, ending balance	0.0
Asset Actions/Other
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	0.0
Current Period Charge	0.0
Cash Payments	0.0
Restructuring reserve, ending balance	$ 0.0