SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) - Allowance for doubtful accounts - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Movement in valuation and qualifying accounts
Balance at Beginning of Period	$ 16.3	$ 18.3	$ 18.9
Additions Charged to Costs and Expenses	5.2	4.7	4.6
Deductions	6.5	6.7	5.2
Amounts Charged to Other Accounts	0.3
Balance at End of Period	$ 15.3	$ 16.3	$ 18.3