Derivatives - Narrative (Detail) - Not Designated as Hedging Instrument - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Accrued Liabilities and Other
Derivative [Line Items]
Derivatives liabilities	$ 3.0	$ 0.3
Prepaid Expenses and Other Current Assets
Derivative [Line Items]
Derivatives assets	0.2	0.9
Foreign Currency Contracts
Derivative [Line Items]
Aggregate notional value	$ 144.4	$ 170.8

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

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Nominal or face amount used to calculate payment on derivative.

+ References

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