Summary of Components of Interest as Presented in Consolidated Statements of Operations (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Debt Instrument [Line Items]
Income	$ 2.5	$ 2.8	$ 8.2	$ 7.0
Expense on borrowings	(35.6)	(29.8)	(105.6)	(88.8)
Income (expense) on UTPs and other tax related liabilities	(2.5)	0.4	(7.0)	(6.3)
Legacy Tax	0.2	0.7	0.2	0.7
Capitalized		0.1	0.4	0.4
Total	$ (35.4)	$ (25.8)	$ (103.8)	$ (87.0)