Discontinued Operations (Schedule of Assets and Liabilities) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Sep. 30, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Plant and equipment	$ 20.0	$ 0.0
Other current assets	0.4	1.8
Total Current Assets	20.4	1.8
Plant and equipment	0.0	891.8
Total Noncurrent Assets	0.0	891.8
Payables and accrued liabilities	43.7	17.0
Other current liabilities	2.8	0.0
Total Current Liabilities	46.5	17.0
Other noncurrent liabilities	0.0	2.5
Total Noncurrent Liabilities	$ 0.0	$ 2.5