Cumulative translation adjustment for net investment hedge.

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- Definition

Debt Instrument Maturity Date Year

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Face (par) amount of the original debt instrument that was repurchased.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The cash outflow for a long-term debt where the holder has highest claim on the entity's asset in case of bankruptcy or liquidation during the period.

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Debt - Additional Information (Detail) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
Debt - Additional Information (Detail) $ in Millions	Oct. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Nov. 09, 2018	Sep. 30, 2018 EUR (€)	Dec. 31, 2017
Debt Instrument [Line Items]
Deferred gain (loss) on net investment hedge recorded in AOCL, net of tax			$ 7.7
Gain related to extinguishment of debt/credit facility				$ (32.3)
Scenario, Forecast [Member]
Debt Instrument [Line Items]
Gain related to extinguishment of debt/credit facility		$ 0.4
Subsequent Event [Member]
Debt Instrument [Line Items]
Consideration for repurchase of debt	$ 893.0
3.75% Senior Notes Due 2021 [Member]
Debt Instrument [Line Items]
Senior notes rate						3.75%	3.75%
Debt Instrument, face amount \| €						€ 300,000,000
Tender Offers [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt instrument, repurchased face amount	$ 1,000.0
2.875% Senior Notes Due 2019 [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Senior notes rate	2.875%
Debt instrument, repurchased face amount	$ 249.0
Debt instrument, maturity date	2019
3.15% Senior Notes Due 2021 [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Senior notes rate	3.15%
Debt instrument, repurchased face amount	$ 650.0
Debt instrument, maturity date	2021
3.85% Senior Notes Due 2023 [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Senior notes rate	3.85%
Debt instrument, maturity date	2023
4.20% Senior Notes Due 2026 [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Senior notes rate	4.20%
Debt instrument, maturity date	2026
2.15% Senior Notes Due 2018 [Member]
Debt Instrument [Line Items]
Senior notes rate						2.15%	2.15%
2.875% Senior Notes Due 2019 [Member]
Debt Instrument [Line Items]
Senior notes rate						2.875%	2.875%
2.875% Senior Notes Due 2019 [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Senior notes rate					2.875%