SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Allowance for doubtful accounts
Balance at beginning of year	$ 2.5	$ 3.0	$ 3.1
Charged to expense	5.2	5.7	7.5
Deductions	5.2	6.2	7.6
Balance at end of year	$ 2.5	$ 2.5	$ 3.0