Disposal of Video Camera Segment (Cohu Electronics) - Summary of Operating Results of Discontinued Video Camera Segment (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012
Discontinued Operations and Disposal Groups [Abstract]
Net sales	$ 5,460	$ 15,726	$ 14,850
Operating income (loss) before income taxes	(242)	1,317	(121)
Gain on disposal of video camera segment	4,434
Income tax provision (benefit)	1,319	475
Income from discontinued operations, net of taxes	$ 2,873	$ 842	$ (121)

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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