Other Assets - Additional Information (Details) - USD ($) $ in Millions	Sep. 30, 2017	Sep. 30, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Long-term debt	$ 5,870.9	$ 5,635.6
Other assets	137.2	138.3
Salus Capital Partners LLC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Long-term debt	$ 22.2	$ 30.3
Credit Concentration Risk [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage Of Accounts Receivable Major Customers	14.00%	15.10%