Disposal of Video Camera Segment - Summary of Operating Results of Discontinued Video Camera Segment (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 28, 2014	Jun. 29, 2013	Jun. 28, 2014	Jun. 29, 2013
Discontinued Operations And Disposal Groups [Abstract]
Net sales	$ 1,907	$ 4,418	$ 5,460	$ 8,207
Operating income (loss) before income taxes	(363)	451	(242)	658
Gain on disposal of video camera segment	4,248		4,133
Income tax provision	653	162	653	237
Income from discontinued operations, net of taxes	$ 3,232	$ 289	$ 3,238	$ 421

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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