Derivative Instruments And Hedging Activities - Fair Value of Derivative Instruments (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivative, Fair Value, Net [Abstract]
Assets	$ 52.3	$ 28.3
Liabilities	574.6	588.0
Long Term Debt [Member] | Net Investment Hedging [Member]
Derivative, Fair Value, Net [Abstract]
Liabilities	561.4	571.6
Derivatives Designated as Accounting Hedges [Member]
Derivative, Fair Value, Net [Abstract]
Assets	52.0	26.9
Liabilities	2.3	8.2
Derivatives Designated as Accounting Hedges [Member] | Interest Rate Swap [Member] | Other Assets [Member]
Derivative, Fair Value, Net [Abstract]
Assets	15.3	7.5
Derivatives Designated as Accounting Hedges [Member] | Interest Rate Swap [Member] | Other Liabilities [Member]
Derivative, Fair Value, Net [Abstract]
Liabilities	2.3	5.3
Derivatives Designated as Accounting Hedges [Member] | Cross-Currency Swap [Member] | Other Assets [Member] | Net Investment Hedging [Member]
Derivative, Fair Value, Net [Abstract]
Assets	36.7	19.4
Derivatives Designated as Accounting Hedges [Member] | Cross-Currency Swap [Member] | Other Liabilities [Member] | Net Investment Hedging [Member]
Derivative, Fair Value, Net [Abstract]
Liabilities		2.9
Not Designated as Accounting Hedges [Member] | Foreign Exchange Forward [Member] | Other Current Assets [Member]
Derivative, Fair Value, Net [Abstract]
Assets	0.3	1.4
Not Designated as Accounting Hedges [Member] | Foreign Exchange Forward [Member] | Accounts Payable And Accrued Liabilities [Member]
Derivative, Fair Value, Net [Abstract]
Liabilities	$ 10.9	$ 8.2