Derivatives - Schedule of Fair Value of Derivatives Designated and Not Designated as Hedges (Detail) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Not Designated as Hedging Instrument | Prepaid Expenses and Other Current Assets
Derivatives Fair Value [Line Items]
Derivatives assets	$ 28.2	$ 7.0
Not Designated as Hedging Instrument | Accrued Liabilities
Derivatives Fair Value [Line Items]
Derivatives liabilities	1.1	0.5
Designated Fair Value Hedges | Other Noncurrent Assets
Derivatives Fair Value [Line Items]
Derivatives assets	2.4	0.0
Designated Fair Value Hedges | Other Non-current Liabilities
Derivatives Fair Value [Line Items]
Derivatives liabilities	$ 0.0	$ 1.2