Financial instruments - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jul. 02, 2017	Jun. 26, 2016	Jul. 02, 2017	Jun. 26, 2016	Dec. 31, 2016
Derivatives Fair Value [Line Items]
Net revenues	$ 528,613,000	$ 473,553,000	$ 1,016,494,000	$ 898,446,000
Spain, Italy, Portugal, and Greece
Derivatives Fair Value [Line Items]
Net revenues			64,500,000	63,700,000
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	73,600,000		73,600,000		$ 101,800,000
Foreign exchange contract | Not Designated as Hedging Instrument
Derivatives Fair Value [Line Items]
Loss related to currency forward contracts	2,300,000	$ 1,300,000	3,100,000	$ 1,600,000
Total notional amount for all open foreign currency forward contracts	$ 92,200,000		$ 92,200,000		$ 73,400,000