Financial Instruments and Hedging Activities (Fair Values of Derivative Instruments Included on Consolidated Balance Sheet) (Detail) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	$ 183.1	$ 205.3
Liability Derivatives Fair Value	(59.2)	(44.4)
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	25.9	60.9
Liability Derivatives Fair Value	(40.8)	(38.9)
Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	157.2	144.4
Liability Derivatives Fair Value	$ (18.4)	$ (5.5)