Derivative Instruments - Information Regarding Effect of Forward Contracts, Net of Underlying Exposure, on Consolidated Statements of Operations (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Apr. 05, 2015	Mar. 30, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Reclassification of net realized (gain) loss into current operations	$ (110)	$ (33)
Designated as Hedging Instrument | Accumulated other comprehensive income (loss), net of tax
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) recorded in shareholders' equity (effective portion)	(378)	(62)
Designated as Hedging Instrument | Product revenue
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) reclassified from accumulated other comprehensive income (loss) into current operations (effective portion)	(152)	13
Designated as Hedging Instrument | Research, development, and engineering expenses
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) reclassified from accumulated other comprehensive income (loss) into current operations (effective portion)	1	(30)
Designated as Hedging Instrument | Selling, general, and administrative expenses
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) reclassified from accumulated other comprehensive income (loss) into current operations (effective portion)	41	(16)
Designated as Hedging Instrument | Foreign currency gain (loss)
Information regarding the effect of the forward contracts, net of the underlying exposure, on the Consolidated Statements of Operations
Gains (losses) recognized in current operations (ineffective portion and discontinued derivatives)	0	0
Not Designated as Hedging Instrument | Foreign currency gain (loss)
Information regarding the effect of the forward contracts, net of the underlying exposure, on the Consolidated Statements of Operations
Gains (losses) recognized in current operations	$ 78	$ (152)