Schedule II- Valuation and Qualifying Account (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at the beginning of year	$ 4.7	$ 5.4	$ 9.5
Charged to (Reversed from) Costs and Expenses	6.5	(0.7)	(3.8)
Write-offs, Net of Recoveries	(1.9)	0.0	(0.3)
Balance at the end of year	9.3	4.7	5.4
Sales Return Reserve [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at the beginning of year	50.2	49.0	52.7
Charged as a Reduction in Revenues	65.4	53.2	35.0
Charged to Other Accounts	92.6	80.9	61.5
Used	(137.0)	(132.9)	(100.2)
Balance at the end of year	$ 71.2	$ 50.2	$ 49.0