Disposal of Video Camera Segment - Summary of Operating Results of Discontinued Video Camera Segment (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 28, 2015	Mar. 29, 2014
Discontinued Operations and Disposal Groups [Abstract]
Net sales		$ 3,553
Operating income before income taxes		121
Loss on disposal of video camera segment		(116)
Income tax provision	0	0
Loss from discontinued operations, net of taxes		$ 5

Amount of gain (loss), after tax expense or benefit and not previously recognized, resulting from the sale of a business component.

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After tax income (loss) from operations of a business component (exclusive of any gain (loss) on disposal, or provision therefore) during the reporting period, until its disposal.

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Income tax expense or benefit attributable to Income or Loss from discontinued operations during the phase-out period.

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Amount of sales or other form of revenues attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Amount of income (loss) from a disposal group, net of income tax before extraordinary items allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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