Financial Instruments and Hedging Activities (Fair Values of Derivative Instruments Included on Consolidated Balance Sheet) (Detail) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	$ 140.8	$ 205.3
Liability Derivatives Fair Value	(27.9)	(44.4)
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	9.7	60.9
Liability Derivatives Fair Value	(11.3)	(38.9)
Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	131.1	144.4
Liability Derivatives Fair Value	$ (16.6)	$ (5.5)