Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Income tax
Estimated effective income tax rate (as a percent)	22.00%		22.00%	18.00%		22.00%	18.00%
Income tax expense for discrete items in continuing operations		$ 1.3		$ 1.3
Unrecognized income tax benefit adjustments affecting discontinued operations							2.7
Period of cumulative accounting profit that may be realized					3 years	3 years
Net operating and capital loss carryforwards	77.3		77.3
Tax credit carryforwards	25.7		25.7
Unrecognized income tax benefits that may be released within next 12 months	$ 1.0		$ 1.0
Minimum [Member]
Income tax
Operating loss carryforwards expiration date			Sep. 30, 2014
Tax credit carryforwards, expiration date			Sep. 30, 2014
Maximum [Member]
Income tax
Operating loss carryforwards expiration date			Sep. 30, 2033
Tax credit carryforwards, expiration date			Sep. 30, 2033