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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
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Amount of decrease in the fair value of derivatives recognized in the income statement.

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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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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Financial instruments - Additional Information (Detail) - USD ($)	3 Months Ended
	Apr. 01, 2018	Apr. 02, 2017	Dec. 31, 2017
Derivatives Fair Value [Line Items]
Net revenues	$ 587,230,000	$ 487,881,000
Spain, Italy, Portugal, and Greece
Derivatives Fair Value [Line Items]
Net revenues	38,300,000	31,500,000
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	117,300,000		$ 88,500,000
Foreign exchange contract \| Not Designated as Hedging Instrument
Derivatives Fair Value [Line Items]
Gain related to currency forward contracts	600,000
Loss related to currency forward contracts		$ 800,000
Total notional amount for all open foreign currency forward contracts	$ 111,500,000		$ 110,600,000