Supplemental Condensed Consolidating Financial Information - Additional Information (Detail) (USD $) In Millions, unless otherwise specified		12 Months Ended
	Dec. 31, 2012 Guarantors	Dec. 31, 2011 Guarantors Interest Expense	Dec. 31, 2011 Guarantors Net Income	Dec. 31, 2011 Guarantors Noncurrent Liabilities	Dec. 31, 2011 Non Guarantors Interest Expense	Dec. 31, 2011 Non Guarantors Net Income	Dec. 31, 2011 Non Guarantors Noncurrent Assets	Dec. 31, 2010 Parent Net Revenue	Dec. 31, 2010 Parent Operating Expense
Supplementary Information [Line Items]
Percentage of ownership interests	100.00%
Statement Adjustment		$ (87.2)	$ 53.8	$ (53.8)	$ 87.2	$ (53.8)	$ (53.8)	$ 0.3	$ 0.3