Financing Agreements (Schedule of Fair Value) (Details) - USD ($) $ in Millions	Jun. 30, 2017	Sep. 30, 2016
Debt Instrument [Line Items]
Total debt	$ 2,194.8	$ 1,940.8
Unsecured Debentures [Member]
Debt Instrument [Line Items]
Fair value of unsecured notes	44.9	45.8
Senior Secured Term Loan A [Member]
Debt Instrument [Line Items]
Senior secured Term Loan A	1,392.9	1,441.0
Senior Unsecured 5.75% Notes due on September 1, 2023 [Member]
Debt Instrument [Line Items]
Fair value of unsecured notes	449.6	454.0
Senior Unsecured 5.00% Notes due on February 14, 2025 [Member]
Debt Instrument [Line Items]
Fair value of unsecured notes	$ 307.4	$ 0.0