Derivatives (Effect of Derivative Financial Instruments on Our Consolidated Statements of Operations) (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	12 Months Ended
	May 31, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Derivative Instruments, Gain (Loss) [Line Items]
Loss recognized in Other Comprehensive Income (Loss) on derivatives		$ 8.2	$ (3.8)	$ (11.1)
Loss reclassified from Accumulated Other Comprehensive Income (Loss) into income (effective portion)		(4.4)
Gain (loss) recognized in income on derivatives (ineffective portion and amount excluded from effectiveness testing)		(3.4)	(1.2)
Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Loss reclassified from Accumulated Other Comprehensive Income (Loss) into income (effective portion)	(2.9)	9.9	18.8	17.2
Gain (loss) recognized in income on derivatives (ineffective portion and amount excluded from effectiveness testing)		$ (3.4)	$ (1.2)	$ 0