Summary of Components of Interest as Presented in Consolidated Statements of Operations (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Debt Instrument [Line Items]
Income	$ 2.8	$ 2.3	$ 5.7	$ 4.2
Expense on borrowings	(35.4)	(30.7)	(70.0)	(59.0)
Income (expense) on UTPs and other tax related liabilities	(1.7)	(3.5)	(4.5)	(6.7)
Capitalized			0.4	0.3
Total	$ (34.3)	$ (31.9)	$ (68.4)	$ (61.2)