Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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The percentage points added to the reference rate to compute the variable rate on the interest rate derivative.

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Fixed interest rate related to the interest rate derivative.

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Amount of decrease in the fair value of derivatives recognized in the income statement.

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The number of derivative instruments of a particular group held by the entity.

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The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Financial instruments - Additional Information (Details)	3 Months Ended
	Mar. 31, 2019 USD ($)	Apr. 01, 2018 USD ($)	Mar. 31, 2019 EUR (€)	Mar. 04, 2019	Dec. 31, 2018 USD ($)	Oct. 04, 2018 USD ($)	Oct. 04, 2018 EUR (€)
Derivatives Fair Value [Line Items]
Foreign currency translation, continuing operations, adjustments, net of tax	$ (236,000)	$ 81,188,000
Net revenues	613,584,000	587,230,000
Cash flow hedging
Derivatives Fair Value [Line Items]
Ineffectiveness related to derivatives	0	0
Foreign exchange contract \| Designated as Hedging Instrument \| Cash flow hedging
Derivatives Fair Value [Line Items]
Total notional amount for all open foreign currency forward contracts	63,400,000				$ 115,300,000
Foreign exchange contract \| Not Designated as Hedging Instrument
Derivatives Fair Value [Line Items]
Loss related to currency forward contracts	3,000,000	$ 600,000
Total notional amount for all open foreign currency forward contracts	132,800,000				$ 125,900,000
Cross-currency interest rate swap \| Cash flow hedging
Derivatives Fair Value [Line Items]
Foreign currency translation, continuing operations, adjustments, net of tax	10,600,000
Cross-currency interest rate swap \| Designated as Hedging Instrument
Derivatives Fair Value [Line Items]
Total notional amount for all open foreign currency forward contracts	$ 250,000,000		€ 219,200,000.0			$ 500,000,000	€ 433,900,000.0
Derivative, number of instruments held				5		6	6
Derivative, fixed interest rate	4.875%		4.875%			4.625%	4.625%
Derivative, annual interest rate	2.4595%		2.4595%			1.942%	1.942%