Fair Value of Derivative Instruments (Detail) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Derivatives Fair Value [Line Items]
Derivatives assets	$ 22.9	$ 7.6
Derivatives liabilities	478.0	427.3
Non-Derivatives Designated as Accounting Hedges [Member] | Net Investment Hedging [Member] | Long Term Debt [Member]
Derivatives Fair Value [Line Items]
Derivatives liabilities	472.9	421.9
Derivatives Designated as Accounting Hedges [Member]
Derivatives Fair Value [Line Items]
Derivatives assets	12.3	7.6
Derivatives liabilities	1.0	4.6
Derivatives Designated as Accounting Hedges [Member] | Cross-Currency Swap [Member] | Other Assets [Member]
Derivatives Fair Value [Line Items]
Derivatives assets	7.3
Derivatives Designated as Accounting Hedges [Member] | Cross-Currency Swap [Member] | Other Liabilities [Member]
Derivatives Fair Value [Line Items]
Derivatives liabilities		3.8
Derivatives Designated as Accounting Hedges [Member] | Interest Rate Swap [Member] | Other Assets [Member]
Derivatives Fair Value [Line Items]
Derivatives assets	5.0	7.0
Derivatives Designated as Accounting Hedges [Member] | Interest Rate Swap [Member] | Other Liabilities [Member]
Derivatives Fair Value [Line Items]
Derivatives liabilities	1.0	0.8
Derivatives Designated as Accounting Hedges [Member] | Net Investment Hedging [Member] | Foreign Exchange Forward [Member] | Other Current Assets [Member]
Derivatives Fair Value [Line Items]
Derivatives assets		0.6
Derivatives Designated as Accounting Hedges [Member] | Net Investment Hedging [Member] | Cross-Currency Swap [Member] | Other Liabilities [Member]
Derivatives Fair Value [Line Items]
Derivatives liabilities		3.8
Derivatives Not Designated as Accounting Hedges [Member] | Foreign Exchange Forward [Member] | Other Current Assets [Member]
Derivatives Fair Value [Line Items]
Derivatives assets	10.6
Derivatives Not Designated as Accounting Hedges [Member] | Foreign Exchange Forward [Member] | Accounts Payable And Accrued Liabilities [Member]
Derivatives Fair Value [Line Items]
Derivatives liabilities	$ 4.1	$ 0.8