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

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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, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Financial instruments - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Oct. 01, 2017	Sep. 30, 2018	Oct. 01, 2017	Dec. 31, 2017
Derivatives Fair Value [Line Items]
Net revenues	$ 609,672,000	$ 534,703,000	$ 1,806,768,000	$ 1,551,197,000
Spain, Italy, Portugal, and Greece
Derivatives Fair Value [Line Items]
Net revenues			107,700,000	96,000,000
Cash flow hedging
Derivatives Fair Value [Line Items]
Ineffectiveness related to derivatives	0	0	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	127,500,000		127,500,000		$ 88,500,000
Foreign exchange contract \| Not Designated as Hedging Instrument
Derivatives Fair Value [Line Items]
Loss related to currency forward contracts	1,000,000	$ 600,000	300,000	$ 3,700,000
Total notional amount for all open foreign currency forward contracts	$ 124,600,000		$ 124,600,000		$ 110,600,000