Valuation and Qualifying Accounts (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Allowance for Doubtful Accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	$ 3.5	$ 3.2	$ 3.1
Charged to cost and expenses	1.6	0.6	(0.1)
Other deductions	(0.9)	(0.3)	0.2
Balance at end of year	4.2	3.5	3.2
Allowance for Volume and Early Payment Discounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	14.6	15.7	15.2
Charged to cost and expenses	57.6	58.4	54.4
Other deductions	(60.1)	(59.5)	(53.9)
Balance at end of year	12.1	14.6	15.7
Allowance for Sales Returns
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	54.5	57.8	59.9
Charged to cost and expenses	77.8	73.7	77.0
Other deductions	(79.2)	(77.0)	(79.1)
Balance at end of year	$ 53.1	$ 54.5	$ 57.8