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Basis of Presentation and Summary of Significant Accounting Policies - Gains (Losses) on Foreign Exchange Contracts (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Cost of Sales [Member] | Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized (losses) gains on closed contracts	$ (23)	$ 2,871	$ (2,181)	$ 3,301
Unrealized (losses) gains on open contracts	(5)	(1,258)	(1,097)	819
Cumulative net pre-tax(losses) gains	(28)	$ 1,613	(3,278)	$ 4,120
Interest Income [Member] | Cross Currency Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest earned	927		927
Stockholders' Equity [Member] | Cross Currency Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized (losses) gains on open contracts	$ 767		$ 767

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

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