Derivative Instruments And Hedging Activities - Fair Value of Derivative Instruments (Detail) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Assets	$ 154.6	$ 28.3
Liabilities	550.8	588.0
Long-term debt | Net Investment Hedging
Derivatives, Fair Value [Line Items]
Liabilities	545.1	571.6
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Assets	154.0	26.9
Liabilities	0.0	8.2
Designated as Hedging Instrument | Cross-currency swap | Other assets | Net Investment Hedging
Derivatives, Fair Value [Line Items]
Assets	116.5	19.4
Designated as Hedging Instrument | Cross-currency swap | Other liabilities | Net Investment Hedging
Derivatives, Fair Value [Line Items]
Liabilities	0.0	2.9
Designated as Hedging Instrument | Interest Rate Swap | Other assets | Fair Value Hedging
Derivatives, Fair Value [Line Items]
Assets	32.8	7.5
Designated as Hedging Instrument | Interest Rate Swap | Other current assets | Fair Value Hedging
Derivatives, Fair Value [Line Items]
Assets	2.3	0.0
Designated as Hedging Instrument | Interest Rate Swap | Other liabilities | Fair Value Hedging
Derivatives, Fair Value [Line Items]
Liabilities	0.0	5.3
Designated as Hedging Instrument | FX forwards | Other current assets | Net Investment Hedging
Derivatives, Fair Value [Line Items]
Assets	2.4	0.0
Not Designated as Accounting Hedges | FX forwards | Other current assets
Derivatives, Fair Value [Line Items]
Assets	0.6	1.4
Not Designated as Accounting Hedges | FX forwards | Accounts payable and accrued liabilities
Derivatives, Fair Value [Line Items]
Liabilities	$ 5.7	$ 8.2