Derivatives and Financial Instruments - Assets and Liabilities Measured at Fair Value (Detail) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill	$ 4,251.7	$ 4,259.0
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign currency contract assets	3.6	0.1
Foreign Currency Contracts, Liability, Fair Value Disclosure	(25.5)	(7.6)
Deferred compensation plan	47.9	50.8
Net Assets and Liabilities Fair Value Disclosure	26.0	43.3
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign currency contract assets	0.0	0.0
Foreign Currency Contracts, Liability, Fair Value Disclosure	0.0	0.0
Deferred compensation plan	41.2	43.8
Net Assets and Liabilities Fair Value Disclosure	41.2	43.8
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign currency contract assets	3.6	0.1
Foreign Currency Contracts, Liability, Fair Value Disclosure	(25.5)	(7.6)
Deferred compensation plan	6.7	7.0
Net Assets and Liabilities Fair Value Disclosure	(15.2)	(0.5)
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign currency contract assets	0.0	0.0
Foreign Currency Contracts, Liability, Fair Value Disclosure	0.0	0.0
Deferred compensation plan	0.0	0.0
Net Assets and Liabilities Fair Value Disclosure	$ 0.0	$ 0.0